Method and apparatus for image representation and/or reorientation

ABSTRACT

An attribute detecting apparatus of data signals obtains a block to which a mapped point belongs, for data signals divided into a plurality of blocks; sequentially repeats mapping processing in such a way that the mapped point belonging to the block is mapped to a similar region in the data signals previously allowed to correspond to the block (by setting an attribute detection position to an initial position of the mapped point and using the preceding mapping point as a new mapped point); and decides the attribute at the attribute detection position on the basis of position data of the mapping points obtained by the repeated mappings. An attribute detecting apparatus suitable for detecting the attributes of the fractal coded video signals can be realized.

BACKGROUND OF THE INVENTION

The present invention relates to method and apparatus for detectingpredetermined attributes (e.g., texture) of data signals (e.g., videoand audio signals), and more specifically to a method and apparatus fordetecting feature patterns of characters or graphics as thepredetermined attributes of video signals (i.e., data signals).

Further, the present invention relates to a method and apparatus for animage segmentation to divide a picture into a plurality of regions torecognize and process the divided regions on the basis of video signallevels, and further to easily represent a boundary of the dividedregions.

First, the prior art technique related to the method and apparatus fordetecting data signal attributes will be described hereinbelow.

(1) As a novel compression coding technique for a grayscale image,fractal coding technique has been so far studied (for instance, asdisclosed by Document 1: "Fractal Image Coding: A Review", A. E.Jacquin, Proceedings of the IEEE, VOL. 81, No.10, October, 1993). Inthis technique, an original square picture to be coded is divided into aplurality of blocks, as shown in FIG. 1, and a coder decides a similarregion or regions for each block on the basis of the other blocks in thesame picture. Here, "similar" implies the relationship between theblocks in which the picture patterns can be roughly equalized to eachother, by a linear reduction transform in the picture, a simple pixelarrangement transform (such as revolution in units of 90 degrees andmirror image reversal, etc.), and a liner transform of pixel values. Theabove-mentioned linear transform is referred to as an affine transform.Here, in the case of digital video signals, since a picture isconstructed by a number of discrete pixels, the reduction transform in apicture is the same as the sampling of pixels.

Now, as shown in FIG. 2, the assumption is made that there exists asimilar region 152 whose vertical and horizontal sizes are twice aslarge as those of a block 151, and the block 151 is composed of 4×4pixels and the similar region 152 is composed of 8×8 pixels. Here, whenthe pixel arrangement is not transformed, for instance, a pixel 153located on the upper left side of the block 151 corresponds to a whitepoint 155 of the similar region 152. However, there exists no pixel atthis position 155. In this case, therefore, the value of the pixel 153is determined by an average value of four pixels 154 surrounding thewhite point 155. As described above, the reduction transform can beobtained by sampling 4×4 pixel data from the 8×8 pixel data.

Further, the fractal coder outputs (a) the position and the sizes of asimilar region for each block, (b) the transform method of pixelarrangement, and (c) the data required for pixel value transform methodas code data. The outputted coded data are transmitted or stored. In thereduction transform method in a picture, since the coded output data canbe decided unequivocally in accordance with the size of the similarregion and the size of the previously determined blocks, it isunnecessary to transmit and store the code data.

FIG. 4 is a block diagram showing a prior art fractal coder. Originalpicture data 301 are stored in a frame memory 302. On the basis of asignal 304 for designating the linear transform applied from a controlsection 303, picture data 305 in a designated region are read from theframe memory 302, and then inputted to a size reduction transformsection 306. The size reduction transform section 306 reduces thepicture data 305 in the region to the same size of the block (i.e., thesame number of pixels of the block). The reduced data 307 aretransmitted to the transform section 308. The transform section 308executes the aforementioned-mentioned linear transforms other than thesize reduction transform, and the transformed data 309 are inputted to adifference section 311. On the other hand, the block data 310 areinputted from the frame memory 302 to the difference section 311. Thedifference section 311 calculates a difference between the block data310 and the transformed data 309, and transmits a difference 312 to acontrol section 303. As described above, the control section 303designates several sorts of linear transforms, and decides the lineartransform of the minimum difference 312 as the similarity transform ofthe block. The decided data are outputted as codes 313 to the outside.

FIG. 3 is a block diagram showing a prior art fractal decoder fordecoding an original picture on the basis of the codes transmitted fromthe fractal coder as described above. In the drawing, codes 501 areinputted to a transform section 502. Further, an original picture ispreviously stored in a frame memory 503. Any images can be used as theoriginal picture. In accordance with the data included in the codes 501,the similar region data 504 for each block are read from the framememory 502. The similar region data 504 are processed in accordance withthe data included in the codes 501. The processing executed by thetransform section 501 is intra-picture reduction transform, pixelarrangement transform, and pixel value transform. The transformed data505 are transmitted to the frame memory 503, and overwritten on thecorresponding blocks of the frame memory 503. The above-mentionedrewriting of pixel values are executed for all the blocks, respectivelyto obtain a first replacement picture. After that, on the basis of thefirst replacement picture, the similar replacement as with the case ofthe first replacement is executed again to obtain a second replacementpicture. After the above-mentioned replacements have been iteratedseveral times, since the picture stored in the frame memory 503 can beconverged to a picture roughly equal to the original picture, theconverged picture is outputted to the outside as a reconstructed image506. The reconstructed image 506 will not change any more even ifreplaced repeatedly. In other words, the following expression can beobtained

    F(A)=A

where A denotes a reconstructed image and F denotes a replacementtransform.

The fact that an image is reconstructed on the basis of the fractalcoding/decoding is to obtain an image A which can satisfy the aboveexpression. In the case where the transform F is the reductiontransform, the conventional method utilizes such a nature that any imagecan approach an image A gradually after the replacement transforms Fhave been iterated.

FIG. 5A is a block diagram showing a prior art fractal decoder. First,any desired initial pictures can be stored in a picture memory 401. Ingeneral, this initial picture is different from an original picture.Input codes 402 are read from a storage medium 403, for instance.Further, similarity region data 405 of the first block are read from thepicture memory 401. The data 405 read from the picture memory 401 aretransformed by a position transform section 404 in accordance with thetransform designated by the position transform codes 406 of the firstblock, and then transmitted to a pixel value transform section 407. Inthe pixel value transform section 407, the transform executed isdesignated by the pixel value transform codes 408 of the first block.The transformed data 409 are returned to the picture memory 401. In thepicture memory 401, the first block pixels are replaced with thetransformed data. The pixel replacement by the similarity transform asdescribed above are executed for the second block and after in the sameway, to obtain the first transformed picture. The obtained picture isdifferent from the original picture in general.

After that, the similar replacement transforms for each block areexecuted by use of the first transformed picture stored in the picturememory 401, to obtain the second transformed picture. By repeating theabove-mentioned replacement transforms, the picture in the picturememory 401 is converged gradually to a picture roughly equal to theoriginal picture. The converged picture is outputted as the reproducedpicture, and then displayed on a display unit 410, for instance.

On the other hand, as the fractal codes represent a geometricalstructure of a picture as codes, it is possible to consider that theattribute at each portion of the video signals can be discriminated, byuse of data of the block and the similar region included in the codes.The discrimination as to which region the pixels in a picture belong tois considered to be effective for division of the picture. The divisionof the picture region can be applied to various fields. For instance,after a picture including a plurality of objects has been divided into aplurality of regions for each object, these regions can be synthesizedagain in any desired arrangement or the sorts of the objects can berecognized on the basis of the shapes of the regions. Further, in thecompression coding of the video signals, it is possible to allocate manybits to only important regions from the visual standpoint, to improvethe subjective picture quality. Therefore, the technique of the imagesegmentation is important as the basic technique for these applications.However, there have been not yet proposed any method of detecting theattributes of the data signals (e.g., original video signals) from thefractal codes and further the method of the image segmentation on thebasis of the detected attributes.

Further, in the prior art method as described with reference to FIG. 3,since the frame memory is required to store pixel values for eachpicture in the fractal decoder, there exists a problem in that theapparatus scale and cost thereof both increase. In addition, when only apart of an image is required to be reconstructed, in the prior artmethod, after the entire image has been once reconstructed, any desiredpart is cut away from the entire image, while discarding the otherremaining portions. In this method, however, wasteful calculations areinevitably executed for the reconstruction of the unnecessary portion,thus it being not preferable from the standpoint of processingefficiency.

Here, in the case where there exists a picture data base (in which agreat number of pictures are stored in the form of fractal coded data)and the stored data base can be retrieved, this will be taken intoaccount.

When any desired picture is found, in general, the picture codes areread from the data base to reproduce the original picture, and the readpicture codes are displayed on the display unit for each picture. Inthis retrieval, however, in many cases it is sufficient when a simplepicture indicative of a rough picture size and luminance value or apicture impression can be seen, without necessarily seeing its ownoriginal picture. Therefore, since the simple picture can be formed by asmaller quantity of calculations and a smaller circuit scale, ascompared with the original picture, it is possible to save the retrievaltime and cost. In particular, when a simple binary picture can beformed, it is possible to display the picture, without use of a highgradation display of higher cost.

Further, when an original picture is processed (e.g., morphing ordeforming), in general an original picture is first reproduced on thebasis of the compressed data; the compressed data are processed inaccordance with the conventional method on the basis of light and darkpicture levels; and the processed picture is compressed again fortransmission or storage. However, when the compression and thereproduction are repeated many times as described above, there exists aproblem in that the picture becomes obscure or distorted, with theresult that the picture quality deteriorates gradually. Further, sincethe coder and the decoder must be both required, there exists a problemin that the hardware scale inevitably increases.

(1) As described above, since the fractal codes include the geometricalstructure of a picture, when the attributes of the respective portionsof the picture and other data signals can be discriminated by use of thedata of the block and the similar region related to the codes, theobtained attributes seem very useful to divide the picture region.However, there have been not yet so far proposed the method of detectingthe attributes of data signals (e.g., the original video signals) fromthe fractal codes and further the method of dividing the region on thebasis of the detected attributes.

Further, in the prior art technique, since the frame memory is requiredto store the pixel values for one picture in the fractal decoder, thereexists a problem in that the system scale and cost thereof increases.Further, when only a part of a picture is required to be reproduced,after the entire picture has been once reproduced, since a desired partis cut way while discarding the other remaining parts, there arisesanother problem in that the wasteful calculations are executed forunnecessary parts, with the result that the processing efficiency is nothigh.

(2) In the prior art picture forming apparatus, even in the case where asimple picture is sufficient (as with the case of a data retrieval froma data base in which a great number of pictures are stored in the formof codes), since an original picture has been so formed, manyreproduction calculations are required to be executed, with the resultthat there arises a problem in that the circuit scale increases and ahigh-costly multi-gradation display unit must be prepared to display apicture.

In addition, when the picture is processed on the light and dark level,such problems arise that the picture quality deteriorates graduallyduring the compression reproduction and further the coder and decoderboth must be prepared.

On the other hand, there exists the following prior art technique forextracting the feature pattern.

Conventionally, the technique of recognizing characters (e.g.,hand-written letters) has been important and widely used in practice inthe fields of mail sorting or the hand-written letter input. In thecurrent technique, however, since it is difficult to cut off thecharacters as a pattern in a unit of one character, the cutting-off ofthe characters is supplemented by recognizing a meaning indicated by thecharacter (knowledge information such as a radical). Here, if thecharacter size can be detected before the processing in which theknowledge information is used, since the succeeding recognition can beexecuted more easily, there exists a need of developing a technique fordetecting the character size.

Further, at the pre-processing of recognition of a picture in which aplurality of textures are mixed (fine patterns are distributeduniformly), there exists a need of detecting the size of each texture.Or else, there exists another need such that a pitch period of an audiosignal is required to be detected to facilitate processing of thesucceeding recognition.

It has been known that the fractal dimensions are used to detect thefeature pattern size of these signals. Here, the fractal dimensions canrepresent a complexity of signals (e.g., video signals) by an identifiervalue (See "Fractal Mathematical Principle", Applied Mathematics I, byYamaguchi, Hata, and Kigami, IWANAMI COURSE, April, 1993). Further,there are some methods of obtaining the fractal dimensions. Here,however, a Blanket-Covering method (one of the fractal dimensionobtaining methods) will be explained hereinbelow (See, T. Peli, V. Tom,B. Lee, "Multi-Scale Fractal and Correlation Signatures for ImageScreening and Natural Clutter Suppression", SPIE vol, 1199, VisualCommun. and Image Processing IV, 1989).

Now, an image curved surface (three dimensional) composed of a set ofdots (each of whose length indicates an intensity of luminance value (aninteger value) at each pixel) and a series {ε_(k) } (k=0, 1, . . . ) ofscale ε_(k) (>0) are considered for the respective pixels in thetwo-dimensional picture plane in a direction perpendicular to thepicture. Further, the above-mentioned image curve is covered with ablanket with a width ε_(k) in a certain scale ε_(k) on both the upperand lower sides thereof. Here, if the upper surface of the blanket overthe pixel (i, j) is denoted by u_(i),j (ε_(k)); if the lower surface ofthe blanket under the pixel (i, j) is denoted by b_(i),j (ε_(k)) ; andif the luminance value (an integer value ) at the pixel (i, j) isdenoted by g_(i),j since u_(i),j (ε₀)=b_(i),j (ε₀)=g_(i),j, the uppersurface u_(i),j (ε_(k)) of the blanket over the pixel (i, j) and thelower surface b_(i),j (ε_(k)) of the blanket under the pixel (i, j) canbe obtained gradually as follows: ##EQU1##

Here, since ε₀ =0, the change B (ε_(k)) of the bright surface of theblanket can be obtained as ##EQU2##

This B (ε_(k)) is referred to as a measure relative to the scale(ε_(k)). In other words, the scale corresponds to a unit for obtainingthe measure B (ε_(k)). As shown in FIG. 5B, when the logarithm of themeasures are taken on the ordinate and the logarithm of ε is taken onthe ordinate, there exists a case where a straight line having agradient a can be obtained. Here, (D=2-a) obtained on the basis of thegradient of the straight line is referred to as fractal dimension.

In general, since the measure is a rate corresponding to a volume orarea determined unequivocally relative to the scale, the linearrelationship obtained when the measure and the scale are both taken inlogarithmic scale is characterized by the fractal dimension.

Conventionally, the method of extracting the feature region of a pictureby use of the fractal dimension as described above has been studied. Forinstance, in Japanese Published Unexamined (Kokai) Patent ApplicationNo. 4-17068, blocks of an object picture is divided gradually intosmaller blocks, until the fractal dimension will not change according tothe size of the divided blocks. In the conventional method using thefractal dimension as described above, however, it has been impossible toextract the regions without block division.

Further, Japanese Published Unexamined (Kokai) Patent Application No.3-269782 discloses the method of extracting the character region fromthe character picture by use of the fractal dimension. In this method,the fractal dimension is obtained at all the pixels in both vertical andhorizontal directions of a picture, and the region indicative of thecharacter region is discriminated on the basis of the fractal dimensionpixel by pixel. However, since the region is divided in unit of pixel,it takes much time, and further it has been impossible to easily specifythe pattern size by grasping the character roughly.

As described above, in the prior art methods, when the size of thefeature pattern of the data signals is required to be detected, thereexists a problem in that the processing is very troublesome and therebycomplicated, with the result that it has been impossible to easilydetect the size of the pattern.

Finally, the prior art technique related to the region division of datasignals will be explained hereinbelow by taking video signals as apractical example of data signals.

The technique for dividing a picture into partial regions (in which thelocal feature of video data (e.g., luminance value, color, etc.) isuniform) is referred to as region division. Conventionally, this regiondivision of a picture has been important technique, and widely appliedto various fields such as video signal coding, video signal processing,character region recognition, etc. However, the region division has beenmainly used when video signals on a plane picture are processed.

Further as a technique related to this region division, there exists atechnique of representing the region boundaries (referred to as regionboundary representation, hereinafter). When data obtained as a result ofregion division are stored, transmitted through a communication path, orutilized as coding, this region boundary representation technique isrequired. Therefore, an important problem is how to represent the regionboundary by use of the smallest possible amount of data, which has beenso far studied.

First, the prior art technique of region division will be describedhereinbelow.

The technique for dividing a picture into partial regions (at which thelocal feature of video data (e.g., luminance value, color, etc.) isuniform) is referred to as region division. Conventionally, this regiondivision of a picture has been important technique, and widely appliedto various fields such as video signal coding, video signal processing,character region recognition, etc. However, the region division has beenmainly used when video signals on a plane picture are processed.

For instance, as a simple region expansion method, the regions aredivided on the basis of the luminance values between the adjacent pixels(See IMAGE ANALYSIS HANDBOOK, Editors: Takagi, Shimoda, Tokyo UniversityPublishers' Assoc. October, 1991). With reference to FIG. 6, theprocessing flow is as follows: the luminance value at a non-classifiedpixel is compared with those of the other adjacent pixels. When adifference between the two is less than a threshold value θ, two pixelsare synthesized (or integrated) and a label is attached thereto. Thesame operation is repeated until the region cannot be synthesized. Thismethod is the most basic and simple method.

Although the region division performance thereof is slightly lower thanthat of the other complicated method, since the threshold value θ is aclear parameter, this method is easy to use.

Further, the region division methods can be classified into anintegration method, a separation and/or integration method and pixelcoupling method by changing the region forming process. Further, thereexists an intermediate method by which the feature space is furtherclassified and after that the region is divided. In these methods,however, where the feature rate to the region has an ambiguity due tothe picture uncleanness or noise, it has been impossible to execute theregion division at a sufficiently high precision. To overcome thisproblem, the regions have been so far divided in combination with therelaxation method for removing the ambiguity. However, it takes muchtime to set many parameters for some pictures, so that it has beendifficult to divide the regions of complicated texture or the regions ofless luminance difference.

Further, there exists a need of utilization of the picture regiondivision such that any region is required to be extracted from thepicture. However, when the boundary of the region requested to extractis of complicated shape, even if the region can be grasped roughly, ithas been difficult to extract a region of complicated shape accurately.

Further, in the method and apparatus for compressing and reproducing apicture by dividing the picture into regions and then coding the dividedregions, since the picture regions are transmitted as the additionaldata, a huge data amount must be processed. Further, as shown in FIG. 7,there exists a method such that a shape I_(s) of a region isapproximated by a simple shape I_(A) to reduce the amount of data.Further, various methods of transmitting the region shapes have beenproposed such that: the regions are divided into several blocks and eachblock is approximated by segments (See "Image Coding by Utilization ofContour Fractal Characteristics" by Suzuki, Sumiyoshi, Miyauchi;Proceedings of TV Society, Vol. 48, No. 1, pp. 69-77, 1994) or thetime-shifted picture regions already obtained are substituted for theregions of an original picture (See "Study of Method of Compensating forBlock Size Movement with reference to Preceding Frame" by Kida,Kawashima, Tominaga, All-Japan Meeting of Communications Society, D-179,March 1993).

Further, when any desired region is extracted from a picture in a system(for retrieving and processing pictures after communications and storageas a data base) in accordance with the prior art picture compressionmethod, it has been necessary to reproduce the picture from thecompressed data and further to re-compress the reproduced data afterprocessing. In addition, when these processing are repeated, thereexists a problem in that the picture quality inevitably deteriorates.

Further, in the method of executing the region dividing on the basis ofluminance, a method of executing the region division recurrently byobtaining adaptive threshold value for division has been proposed (See"Recurrent decision method of density threshold and edge detectingthreshold on the basis of match evaluation between contour and edge, byGoto, Toriu, Proceedings of Electron Information Communications D-11,Vol. J77-D-II, No. 9, pp. 1727-1734, September, 1994). In these methods,however, there exists a problem in that it takes much time to set manyparameters according to a picture or a region of complicated texture isdivided too finely, or a region of less difference in luminance cannotbe well divided, etc.

The prior art technique related to the region boundary representationwill be explained herein below.

The well known method of representing a region boundary is chain codingmethod (See IMAGE ANALYSIS HANDBOOK, Editors: Takagi, Shimoda, TokyoUniversity Publishers' Assoc. October, 1991). In this method, thedirections that the boundary extends from a starting point aredescribed. This method is effective as the method of describing thecontour of a region picture. However, in order to express the regionboundary in detail at one-pixel precision, there exists such a problemin that several bits are required for each bit as the data forrepresenting the extending direction of the region boundary.

Further, as one of the fractal coding, there exists Recurrent IFS codingmethod for coding line drawings after the region boundary has beenextracted" (See M. F. Barnsley, A. E. Jacquin, "Application of recurrentiterates function systems to image", SPIE VOL. 1001, VisualCommunications and Image Processing, '88, pp. 122-131). In this method,as shown in FIG. 10, a region boundary 8 is divided by several segments9 corresponding to the afore-mentioned fractal coding block, and thetransform parameters 11 for the similar segments 10 corresponding to asimilar block are obtained. In this method, however, there existproblems in that the region boundary 8 is detected by use of anothermethod and further the division of the segment 9 and the transformparameters 11 for the similar segments 10 must be both obtainedmanually, that is, the coding is not automatized. In addition, it isnecessary to transmit all the broken points 12 (double circles in FIG.10) of the firstly divided segment. Further, in order to express a moredetailed region boundary, the segment must be divided more finely formore accurate retrieval of the similar segments, thus causing drawbackssuch that the number of the broken points 12 increases and thereby thedata representative of positions inevitably increases.

SUMMARY OF THE INVENTION

With these problems in mind, therefore, it is a first object of thepresent invention to provide a method and apparatus for detectingattributes of data signals suitable for detecting attributes of fractalcoded data signals.

Further, a second object of the present invention is to provide apicture forming apparatus for forming a simple picture.

Further, a third object of the present invention to provide a method andapparatus for easily detecting a size of a signal feature pattern.

Further, a fourth object of the present invention is to provide a methodand apparatus for calculating attributes used for discrimination and fordeciding pixel attributes at the same time. In this connection, in theprior art method, the attribute used for discrimination is decided bymanual operation, or by calculating another clustering.

Further, a fifth object of the present invention is to provide a methodand apparatus for reproducing a picture and for dividing the reproducedpicture into regions at the same time. In this connection, in the priorart method, the picture reproduction and the region division areexecuted separately.

Further, a sixth object of the present invention is to provide a methodand apparatus for representing a region boundary in detail by use of asmall number of bits. In this connection, in the prior art method, ithas been difficult to extract a detailed region boundary and torepresent the detailed region boundary by use of a small number of bits.

(1) To achieve the first object, the first aspect of the presentinvention provides a method of detecting an attribute of data signals,comprising the steps of: dividing data signals into a plurality ofblocks; allowing a similar region of the data signals to correspond toeach of the divided blocks; defining mapping from a mapped point in theblock to a mapping point in the similar region corresponding to theblock, for each block; repeating the mapping in sequence by setting anattribute detection position of the data signals to an initial positionof the mapped point and further by setting the preceding mapped point asa new mapped point; and deciding the attribute of the attributedetection position of the data signal on the basis of movement of themapped points.

(2) Here, when the data signals are video signals each having a pixelvalue at each pixel, the mapped point is defined by a position on apicture plane of the video signals and a pixel value direction thereat;and a pixel value component is decided as the pixel value at theattribute detection position at such an initial position that the pixelvalue component at the mapped point obtained by setting the attributedetection position to the initial position will not diverge by therepeated mapping.

(3) Further, the first aspect of the present invention provides anattribute detecting apparatus of data signals, comprising: means forobtaining a block to which a mapped point belongs, for data signalsdivided into a plurality of blocks; mapping means for sequentiallyrepeating mapping such that the mapped point belonging to the blockobtained by the obtaining means is mapped to a similar region in thedata signals previously allowed to correspond to the block, by settingan attribute detection position to an initial position of the mappedpoint and by using the preceding mapped point as a new mapped point; andattribute deciding means for deciding the attribute at the attributedetection position on the basis of position data at the mapped pointsobtained when the mapping are repeated by said mapping means.

(4) Here, when the data signals are video signals each having a pixelvalue at each pixel; the mapped point is defined by a position on apicture plane of the video signals and a pixel value direction thereat;and said attribute deciding means decides a pixel value component, asthe pixel value at the attribute detection position, at such an initialposition that the pixel value component at the mapped point obtainedwith said mapping means by setting the attribute detection position tothe initial position will not diverge.

(5) Further, the attribute deciding means comprises means for detectingpixel value component at such an initial position that the pixel valuecomponents at the mapped points will not diverge in a positive directionwhen the mapping is repeated; means for detecting pixel value componentsat such an initial position that the pixel value components at themapped points diverge in an negative direction when the mapping isrepeated; and pixel value deciding means for deciding a boundary valuebetween the pixel value components diverging in a positive direction andthe pixel value components diverging in an negative direction, as apixel value at the attribute detection position.

(6) Further, the mapping means executes predetermined mapping N-time,and the attribute deciding means comprises storing means for storingblock data generated during the repeated mapping in sequence; means forsetting an initial value as the pixel value; means for reading blockdata from the storing means in the reverse direction; pixel valuetransform means for transforming the pixel value in sequence N times byuse of the read pixel value transform data from the similar region tothe corresponding block; and pixel value deciding means for deciding theoutput of the pixel value transforming means as the pixel value at theattribute detection position.

(7) Further, to achieve the second aspect of the present invention, thepresent invention provides picture forming means comprising: when anoriginal picture is composed of a plurality of coded unit regions, forforming a simple picture of the original picture on the basis of atleast one of position transform data and the pixel value transform dataselected from the similarity transform data for each predetermined codedunit region.

(8) Here, the simple picture forming means comprises edge detectingmeans for detecting an edge of an object in a picture on the basis ofthe position transform data, and means for forming a simple picture bysynthesizing the edges.

(9) The edge detecting means obtains the fixed transform points of eachcoded unit region on the basis of the position transform data, to obtainan edge by collecting the fixed points or by connecting the fixedpoints.

(10) Further, the edge detecting means obtains vectors indicative of themovement direction due to the position transform on the basis of theposition transform data for a plurality of coded unit regions, to decidethe position at which the vector directions match each other as an edge.

(11) Further, the simple picture forming means comprises texture pictureforming means for forming a texture picture on the basis of the pixelvalue transform data.

(12) The texture picture forming means comprises means for formingposition transform again, to from a picture on the basis of both theformed position transform data and the pixel value transform data.

(13) Further, the image forming apparatus of the second aspect of thepresent invention comprises input means for inputting manually affinetransform data for each coded unit region of a picture composed of aplurality of coded unit regions, and means for forming a picture by useof the input affine transform.

(14) The picture forming apparatus of the second aspect of the presentinvention comprises means for reading previously obtained affinetransform data of a picture composed of a plurality of coded unitregions, and transform correcting means for modifying the read affinetransform data partially. Here, the transform correcting means changesthe coded values indicative of the position transform data.

(15) Further, the transform correcting means changes the coded valuesindicative of the pixel vale transform data.

(16) Further in the input means or the transform correcting means forinputting the affine transform data, the affine transform data areinputted or corrected in such a way as to vary slightly with the lapseof time. In the same way, the picture forming means forms a movingpicture which changes in sequence with the lapse of time.

(17) Further, the picture forming apparatus of the second aspect of thepresent invention comprises coding means for outputting the inversetransform data as the affine transform data in such a way that an errorbetween an enlarged transformed picture data of the coded unit region ofthe picture composed of a plurality of coded unit regions and thepicture data of the similar region can be minimized.

(18) Further, the signal feature pattern size detecting apparatusaccording to the present invention comprises: storing means for storinginput signals; scale setting means for setting a plurality of scales forthe input signals; measure detecting means for detecting measures of theinput signals in each of the set scales; and proper size deciding meansfor deciding a proper size of the input signals on the basis of thedetected measures.

(19) Further, in the signal feature pattern size detecting method of thepresent invention, the input signals are stored; a plurality of scalesare set for the input signals; measures of the input signals in each ofthe scales are obtained; and a proper size of the input signals isdecided on the basis of the obtained measures.

(20) Further, in the picture region dividing methods according to thepresent invention; the data signals are video signals and the attributeis a region in a picture; and the apparatus further comprises method ofdividing a picture region on the basis of a detected image regionincluding the steps of: a fractal coding step of dividing one pictureinto a plurality of blocks and obtaining a mapping to each of thesimilar regions allowed to correspond to each of all the divided blocks;a mapping point deciding step of obtaining a plurality of mapping pointsin sequence by executing a predetermined transform processing pluraltimes in accordance with the attribute, beginning from the initial pointdefined as a specific point on coordinates on the basis of apredetermined attribute; a mapping discriminating step for obtaining themapping to the similar region corresponding to the block, from a blockhaving the transformed mapped point; an attribute content deciding stepfor deciding a predetermined attribute content at the initial point onthe basis of the mapped points obtained by the transform processingexecuted plural times; and a feature region dividing step for dividing aregion corresponding to the mapping, as a specific feature region, inaccordance with the predetermined attribute obtained in the attributecontent deciding step.

Further, in the present invention, it is possible to decide theattribute of the initial point and to divide the picture, bytransforming the initial point by a predetermined mapping several timesand by use of at least two of a plurality of mapped points obtainedduring a plurality of transform processing.

Further, in the present invention, it is possible to decide theattribute at the initial point and the pixel value at the initial pointsimultaneously, by transforming the initial point by a predeterminedmapping and on the basis of the obtained mapping.

Further, in the present invention, in a picture divided into a pluralityof blocks, after mapping to each of the similar regions in the picturecorresponding to each of the blocks has been obtained for all theblocks, and in a picture region dividing method for obtaining the mappedpoints a_(n+1) by setting a₀ to the initial point and by use of themapping corresponding to the block having mapped point a_(n) (n=0, . . ., N-1) and further for obtaining the attribute at the initial point byuse of the mapped points a_(n) (n=1, . . . , N); a block having both theattribute at a point in an object region and the attribute at a point ina region other than the object region is detected from the regionsindicated by the attribute; and a region boundary can be represented bydeciding the block position and the mapped point defined in the block,as boundary data.

In the constructions (1) to (20) as described above, the followingeffects can be obtained:

(1) In the first aspect of the present invention, the mapping of themapped point can be decided unequivocally on the basis of the positionalrelationship between the block and the similar region. Here, since theattribute detection position is determined as the initial position, themapping from the mapped point is repeated. The movement of the mappedpoint during the mapping can be classified according to the status ofthe block and the similar region, that is, converges or converged to aperiodic track or moves in chaos. Further, if does not move in chaos norperiodically, the mapped point moves roughly along a specific shape, ormoves only within a constant region. Further, when other componentsexist at the mapped point, the components diverges, converges to aconstant value, vibrates or others. On the basis of the correspondencebetween the classification of the movement of the mapped point and theattribute at the attribute detection position, the attribute can bedecided.

(2) When the data signals are video signals, since the pixels correspondto the respective positions in a picture one by one, the mapped pointcan be defined by three dimensions of the position (x, y) and the pixelvalue (z). Further, the mapping from the block to the similar region isa combination of the transform of the pixel position and the transformof the pixel value. Here, if the mapping is repeated by setting thepixel value of a reconstructed picture to an initial value, the pixelvalue will not diverge. However, if the mapping is iterated from thepixel value slightly dislocated away from the reconstructed picture, thepixel value component at the mapped point diverges. Therefore,inversely, it is possible to obtain the reconstructed value for eachpixel, without use of a frame memory unit, by finding out the pixelvalue at an initial position at which the pixel value component will notdiverge when the mapping is iterated, independently for each pixel.

(3) In the mapping means, the mapping from the mapped point is repeatedby setting the attribute detection position to the initial position, theblock to which the mapped point belongs is obtained for each mapping,and the mapping is executed from the block to which the mapped pointbelongs to the similar region corresponding to the block. Here, sincethe mapping results can be classified into several cases, the attributedeciding means can decide the attribute by finding the correspondingrelationship between the classified mapping result and the attribute atthe attribute detection position.

(4) When the data signals are video signals, since the pixel valuecorresponds to each pixel position in a picture, and the position andthe pixel value can be defined by three-dimensional mapped point. In theattribute deciding means, the pixel value of the reproduced picture candecide by the pixel value deciding means for deciding the pixel valuecomponent as the pixel value at the attribute detection position, atsuch an initial position that the pixel value component at the mappedpoint will not diverge by the mapping means.

(5) The attribute means detects the pixel value component at such aninitial position that the pixel value components at the mapped pointdiverge in a positive direction by the repeated mapping, and further thepixel value component at such an initial position that the pixel valuecomponents at the mapped point diverge in an negative direction by therepeated mapping. As a result, a boundary value between the pixel valuecomponents diverging in a positive direction and the pixel valuecomponents diverging in an negative direction can be obtained. Here,since the mapped point which will not diverge lie between the positivediverging mapped point and the negative diverging mapped point, it ispossible to obtain the reproduced value for each pixel without use onany frame memory by deciding the boundary between both as the pixelvalue of the picture.

(6) In the mapping means, the mapping is iterated predetermined N times.In the attribute deciding means, the block data obtained during therepeated processing of the mapping are first stored in sequence in thestoring means. Secondly, the initial pixel value is set. Any value canbe decided as the initial pixel value when the N is sufficiently large.Further, the block data are read from the storing means in the reversesequence. The pixel value transforming means executes the pixel valuetransform N times in the reverse sequence of the mapping means by use ofthe pixel value transform data from the similar region (corresponding toblock) to the block. By the processing, when returning to the attributedetection position, since the pixel value becomes the pixel value of thereproduced picture, it is possible to decide the transformed result asthe pixel value at the attribute detection position. Therefore, since amemory for storing only the processed block in sequence is necessary(memory capacity is very smaller than that of the frame memory), it ispossible to obtain the reproduced value for each pixel in spite of amemory whose capacity is fairly smaller than that of the conventionalone.

(7) In the image forming apparatus of the second aspect of the presentinvention, a simple picture of an original picture can be formed by useof at least one position transform data or the pixel value transformdata of the affine transform data for each coded unit region. Therefore,since it is unnecessary to use all the affine transform data, a picturecan be formed by a smaller hardware scale.

(8) Further, since the position transform data originally include edgedata of an object in the picture, the object edge can be obtained by useof an appropriate algorithm. Further, when the obtained edges aresynthesized, a simple picture can be obtained. Further, since the edgepicture can be represented as a binary picture, a low-costly binarydisplay can be used.

(9) Further, as the algorithm for obtaining the edge, the fixed pointsof the position transform in each coded unit region are obtained. Here,the fixed point is a point which will not change after transformed.Since the fixed points of the position transform lie on the edge, anedge can be obtained by collecting the fixed points or by connecting thefixed points.

(10) Further, as the algorithm for obtaining the edge point, vectors(referred to as flow vectors, hereinafter) indicative of the movementdirection (i.e., to which position each pixel is transformed and thenmoved) due to the position transform on the basis of the positiontransform data are obtained for a plurality of the coded unit regions.There exists a nature that the direction of the edge matches thedirections of flow vectors at the edge portion (however, there existsthe case where the direction is opposite to each other). Therefore, whenthe flow vectors are obtained by the position transforms for a pluralityof coded unit regions for each pixel, the portion at which thedirections of the flow vectors match each other can be determined as theedge portions.

(11) Further, since the pixel value transform data originally includethe texture data, a texture image can be formed by use of an appropriatealgorithm, so that a simple picture can be formed by a small-scalecircuit.

(12) Further, as the algorithm for obtaining the texture, the positiontransform is set at random. By doing this, it is possible to form atexture image on the basis of the position transform and a previouslyobtained pixel value transform data.

(13) In the picture forming apparatus of the second aspect of thepresent invention, since the similarity transform can be set manually inany desired way for each coded unit region, the picture can be processedin the compressed-picture code level, so that it is possible to preventthe picture deterioration due to repeated compression and reproductionand further to eliminate the coder.

Further, the predetermined similarity transform data can be read and theread similarity transform data can be changed partially. Therefore, whenan already-existing picture is required to be modified, it isunnecessary to input all the similarity transform data from the first.

(14) In the transform correcting means, it is possible to deform theshape of an object by changing the code value representative of theposition transform data.

(15) In the transform correcting means, it is possible to change thelight and dark pattern of a picture, an impression when seen, and thepicture quality can be changed by changing the code valuesrepresentative of the pixel value transform data, in particular.

(16) In the similarity transform data input means or the transformcorrecting means, since the affine transform data changing slightly withthe lapse of time can be set, it is possible to form pictures changingslightly in sequence with the lapse of time by the picture formingmeans. When the affine transform changes, since the formed picturechanges continuously, a smooth moving picture can be formed.

(17) In the picture forming apparatus of the second aspect of thepresent invention, when the affine transform is decided, an inverseenlarge transform is decided as the affine transform in such a way thatan error between the picture data obtained by enlarge-transformingpicture data of the coded unit region and the picture data of thesimilar region can be minimized. Here, when the picture is enlarged byuse of codes, the codes related to the position and the magnitude of thesimilar region (of the position transform data included in the affinetransform data) are multiplied by a constant time. Here, when the codesdecided by use of the reduction-transformed picture (as with the case ofthe conventional coder) are used, the enlarged picture is distortedslightly. In contrast with this, in the present invention, since theerror is compared on the basis of the level of the actually-enlargedpicture, it is possible to prevent a fine distortion not existing on theoriginal picture from being formed.

(18) and (19) As described above, according to the present invention,the input signals are stored; a plurality of scales are set to thestored input signals; the measures of the input signals are obtained ineach of a plurality of the set scales; and the proper sizes of the inputsignals are obtained on the basis of the obtained measures. Therefore,being different from the conventional method, it is unnecessary toexecute the image segmentation, so that the signal feature pattern sizecan be detected easily.

(20) The picture is divided into a plurality of blocks, and the mappingis defined as follows: a point is transformed to a similar region in apicture (which has been previously allowed to correspond to the block towhich the point belongs), by the means for obtaining the block having apredetermined point.

The coordinates of the initial point are transformed several times by apredetermined mapping, so that a mapped point can be obtained for eachtransform, that is, a plurality of mapped points can be obtained. Themapped point can be obtained by the mapping allowed to correspond to theblock having the transformed point. At least two of the mapped pointsare used in a plurality of the obtained mapped points. In other words,in the present invention, even if the mapped points obtained midway isused, during the processing for obtaining the final mapped pointobtained as a result of the final transform, it is possible to executeclustering, which is different from the conventional method. Therefore,as far as the two points can be transformed to the attribute regionhaving the other points in the picture, the attribute of the points canbe decided, so that the picture can be divided for each attributerelated to the point.

Here, since a pixel corresponds to a position of a pictureunconditionally, the point can be defined by the three dimensions of theposition (vertical and horizontal) and the pixel value. On the basis ofthe relationship between the block and the similar region, the pointmapping can be determined unambiguously, and the point mapping isrepeated. The movement of the mapping points can be classified intoseveral cases according to the status of the block and the similarregion as follows: the mapping points converges to a periodic track or apoint or moves in chaos. Further, the mapping point moves along aspecific shape or moves around only within a constant region. Therefore,it is possible to decide the attribute of the initial point beforetransform by allowing the classified result to correspond to theattribute at the initial point. Further, when the movement of the pointsare in the same region, the mapped points move around the same region insuch a way as to be entangled. Therefore, it is possible to allow arange (in which a representative point moves) to correspond to oneattribute, and further to decide the other mapped points moving in thesame range as the same attribute.

Further, after the initial point has been transformed by a predeterminedmapping, the attribute at the initial point can be decided from themapped point. At the same time, the pixel value at the initial point canbe decided by the mapped point. As a result, the attribute and the pixelvalue of the picture can be decided simultaneously.

The initial point arranged in a picture plane and stored in the storingmeans and the mapping data defined for the initial point are bothinputted to the transform means. The initial point is transformedrepeatedly several times by mapping, and then stored in the storingmeans. Further, the mapped points outputted from the storing means areinputted to the attribute deciding means, so that a plurality of theattribute at the initial point can be decided. The attributes outputtedby the attribute deciding means are inputted to the dividing means. Thedividing means outputs the division results of the region of thepicture. Further, at the same time, the mapped points outputted from thesame storing means are inputted to the pixel value deciding means todecide the pixel value at the initial point corresponding to the mappedpoint, so that a reproduced picture can be outputted.

When the above-mentioned transform is repeated beginning from apredetermined pixel value, the pixel values can be reconstructed. On thebasis of the relationship between the block and the similar block, it ispossible to obtain the mapped point at the pixel included in the block.When the mapped point are further mapped repeatedly, if the mappedpoints match the pixel values of the reconstructed picture, thetransformed pixel values will not diverge. However, if do not match, thetransformed pixel values diverge. Therefore, it is possible toreconstruct the picture by obtaining the pixel values which will notdiverge by the repeated mapping. Here, since the mapping for reproducingthe picture and the mapping for obtaining the attribute are the samemapping as already described, the transform means and the storing meanscan be used in common. Therefore, it is possible to execute thetransform for reproducing the picture and the transform for obtainingthe mapped points at the same time.

Further, when the image segmentation method according to the presentinvention is used in particular as the method of extracting andrepresenting only the region boundary, the following functions can beobtained:

The picture is divided into a plurality of blocks, and the mapping isdefined as follows: a point is transformed to a similar region in apicture (which has been previously allowed to correspond to the block towhich the point belongs), by the means for obtaining the block havingthe given point.

The coordinates of the initial point are transformed several times by apredetermined mapping, so that a mapped point can be obtained for eachtransform, that is, a plurality of mapped points can be obtained. Themapped point can be obtained by the mapping allowed to correspond to theblock having the transformed point. By use of these mapped points, theclustering is executed to decide the region representative of theattribute (referred to as a cluster region, hereinafter). With respectto the mapped points other than the points used for the clusterdecision, the attribute of the cluster region obtained by the iteratedtransforms is decided as these points. As a result, all the attributesat all the points in the picture can be decided, so that the picture canbe divided for each attribute. The blocks having the boundary of thedivided blocks can be detected. The detection results and the mappeddata are both inputted to the control means, and the mapping allowed tocorrespond to the detected block is outputted. Finally, the regionboundary can be represented by two of the mapping and the block positionhaving the region boundary.

To represent the region boundary in detail in accordance with the priorart method, a huge code quantity has been so far required. In thepresent invention, however, it is possible to represent a fine boundarywithout increasing the quantity of codes of the mapping and the positionof the block having the boundary.

As explained above, in the first aspect of the present invention, sincethe attribute of the fractal-coded data signals can be detected, it isextremely effective when a picture is required to be divided. Further,since no frame memory is needed, the apparatus scale and the costthereof can be both reduced. In addition, when a part of the picture isrequired to be reconstructed, since only the necessary region can bedivided, it is possible to provide an attribute detecting method andapparatus of high processing efficiency, without executing wastefulcalculations.

In the second aspect of the present invention, since a simple picturecan be formed, when a data base is required to be retrieved, forinstance, it is possible to decrease the quantity of calculations andthereby to reduce the hardware scale, without use of any high-costlymulti-gradation display unit. Further, when the simple picture isprocessed as it is, since the picture quality will not deteriorate dueto the compressed code reconstruction, (being different from the priorart method for processing a picture on the basis of the grayscalelevel). Further, since both the coder and decoder are not required, itis possible to provide a picture forming apparatus for processingpictures by a simple hardware construction.

As described above, in the present invention, the signal feature patternsize can be detected easily. Further, the picture can be divided intoregions in spite of a relatively small quantity of calculations.Further, when the fractal-coded compressed data are used, the imagesegmentation and the image reconstruction can be executed at the sametime.

Further, a fine region boundary can be extracted and further theextracted region boundary can be represented effectively.

BRIEF DESCRIPTION OF THE DRAWINGS

In the attached drawings:

FIG. 1 is an illustration showing the state in which a picture isdivided into a plurality of blocks:

FIG. 2 is an illustration for assistance in explaining the prior artsub-sampling;

FIG. 3 is a block diagram showing a prior art fractal decoder;

FIG. 4 is a block diagram showing a prior art fractal coder;

FIG. 5A is a block diagram showing another prior art fractal decoder;

FIG. 5B is a graphical representation showing a prior art method ofobtaining fractal dimensions on the basis of measures;

FIG. 6 is an illustration showing an example of a prior art regiondivision;

FIG. 7 is an illustration showing an example of a prior art method ofrepresenting a region shape;

FIGS. 8(a) and 8(b) are illustrations for showing a principle of theprior art fractal compression and fractal reproduction;

FIG. 9 is a block diagrams showing the prior art apparatus constructionfor reproducing the pixel values and deciding the attributes;

FIG. 10 is an illustration showing another prior art example of themethod of representing the region boundary;

FIG. 11 is a block diagram showing the construction of a firstembodiment of the attribute detecting apparatus according to the presentinvention;

FIG. 12 is a characteristic diagram showing a one-dimensional signaldivided into blocks in the first embodiment of the apparatus;

FIG. 13 is an illustration showing an input picture for assistance inexplaining the feature of mapping using the fractal codes;

FIGS. 14(a) to 14(c) are illustrations showing the mapping procedure forassistance in explaining the feature of mapping using the fractal codes;

FIG. 15 is an illustrations showing the final process for assistance inexplaining the feature of mapping using the fractal codes;

FIG. 16 is a flowchart showing a procedure of the first embodiment ofthe attribute detecting method according to the present invention;

FIG. 17 is a flowchart showing another procedure of deciding the regionto which the attribute detection position belongs, in the firstembodiment of the attribute detecting method according to the presentinvention;

FIG. 18 is a block diagram showing the construction of a secondembodiment of the attribute detecting apparatus according to the presentinvention;

FIG. 19 is a block diagram showing the construction of a thirdembodiment of the attribute detecting apparatus according to the presentinvention, which is suitable for decoding a picture;

FIG. 19A is a flowchart showing an image reconstructing methodcorresponding to the apparatus shown in FIG. 19;

FIG. 20 is an illustration showing a mapping from a block to a similarregion in the third embodiment according to the present invention;

FIG. 21 is an illustration showing the state where the mapping isrepeated;

FIG. 22 is an illustration showing the state where the pixel valuesdiverge;

FIG. 23 is a block diagram showing the construction of a fourthembodiment of the attribute detecting apparatus according to the presentinvention;

FIG. 24 is a block diagram showing the construction of a fifthembodiment of the attribute detecting apparatus according to the presentinvention;

FIG. 25 is a block diagram showing the construction of a sixthembodiment of the attribute detecting apparatus according to the presentinvention;

FIGS. 26 and 27 are illustrations showing a similar region in the sixthembodiment of the attribute detecting apparatus according to the presentinvention, respectively;

FIGS. 28 and 29 are illustrations showing a fixed point in the sixthembodiment of the attribute detecting apparatus according to the presentinvention, respectively;

FIG. 30 is a block diagram showing the construction of a seventhembodiment of the attribute detecting apparatus according to the presentinvention;

FIGS. 31 and 32 are illustrations showing an edge in the seventhembodiment of the attribute detecting apparatus according to the presentinvention, respectively;

FIG. 33 is a block diagram showing the construction of an eighthembodiment of the attribute detecting apparatus according to the presentinvention;

FIGS. 34 and 35 are illustrations showing flow vectors in a ninthembodiment of the attribute detecting apparatus according to the presentinvention, respectively;

FIG. 36 is an illustration showing a similar region in the ninthembodiment of the attribute detecting apparatus according to the presentinvention;

FIG. 37 is an illustration showing flow vectors in the ninth embodimentof the attribute detecting apparatus according to the present invention;

FIG. 38 is an illustration showing overlapped flow vectors in the ninthembodiment of the attribute detecting apparatus according to the presentinvention;

FIG. 39 is an illustration showing a construction of a modification inthe ninth embodiment of the attribute detecting apparatus according tothe present invention;

FIG. 40 is an illustration showing a construction of the decoder in atenth embodiment of the attribute detecting apparatus according to thepresent invention;

FIG. 41 is an illustration showing a construction of the decoder in aneleventh embodiment of the attribute detecting apparatus according tothe present invention;

FIGS. 42 and 43 are illustrations for assistance in explaining aposition change between before and after position transform by thedecoder of the eleventh embodiment of the present invention;

FIG. 44 is a series of illustrations showing the status where a figureis changed gradually in the eleventh embodiment of the presentinvention;

FIGS. 45 and 46 are illustrations for assistance in explaining a picturechange between before and after pixel value transform by the decoder ofthe eleventh embodiment of the present invention;

FIGS. 47(a), 47(b) and 47(c) are illustrations showing for assistance inexplaining a picture formation process by giving a block average valueand an edge, respectively, by the decoder of the eleventh embodiment ofthe present invention;

FIG. 48 is an illustration showing a construction of the coder in atwelfth embodiment of the attribute detecting apparatus according to thepresent invention;

FIG. 49 is a block diagram showing the construction of a signal featurepattern size detecting apparatus of a thirteenth embodiment of theattribute detecting apparatus according to the present invention;

FIG. 50 is a flowchart for assistance in explaining the operation of thethirteenth embodiment of the size detecting apparatus according to thepresent invention;

FIG. 51A is an illustration showing an example of a measure detectingmethod of the thirteenth embodiment;

FIG. 51B is a graphical representation showing an example of specificsize detecting method on the basis of the measure change rate;

FIGS. 52(a), 52(b) and 52(c) are illustrations for assistance inexplaining the principle of the specific size detecting principle;

FIG. 53 is a graphic representation showing the principle of thespecific size detecting principle;

FIGS. 54(a) and 54(b) are illustrations for assistance in explainingthat the distance between the picture end and any desired region can bedetected by a specific size;

FIGS. 55(a) and 55(b) are illustrations for assistance in explaining thecase where the present invention can be used as the texture analysis;

FIGS. 56(a) and 56(b) are illustrations for assistance in explaining anexample in which any desired region can be detected on a picture;

FIGS. 57(a) to 57(f) are illustrations for assistance in explainingexamples in which any desired region can be detected on a picture;

FIG. 58 is a block diagram showing the fourteenth embodiment of thesignal feature pattern size detecting apparatus according to the presentinvention;

FIGS. 59(a) to 59(c) are illustrations showing an example for detectingedges on the basis of the fourteenth embodiment of the size detectingapparatus according to the present invention;

FIG. 60 is a flowchart showing a basic concept of the picture regiondividing method according to the present invention;

FIGS. 61(a) to 61(c) are illustrations for assistance in explaining themotion of the mapping points due to point coordinate transform by thepicture region dividing method according to the present invention;

FIG. 61A is a block diagram showing an image segmentation apparatusaccording to the present invention;

FIGS. 62(a) and 62(b) are illustrations for assistance in explaining theprinciple of the picture region dividing method according to the presentinvention;

FIG. 63 is a flowchart showing an algorithm of a fifteen embodiment ofthe picture region dividing method according to the present invention;

FIG. 63A is a block diagram showing an image segmentation apparatusaccording to the present invention;

FIGS. 64(a) to 64(d) are illustrations showing examples of clustering inthe fifteenth embodiment of the picture region dividing method accordingto the present invention;

FIG. 65 is a block diagram showing an example of the fifteenthembodiment of the picture region dividing method according to thepresent invention;

FIG. 66 is a graphical representation showing the change of theluminance value in the picture region dividing method according to thepresent invention;

FIG. 67 is a flowchart showing an algorithm for the picture regiondividing method according to the present invention;

FIG. 68 is a block diagram showing a construction of the picture regiondividing apparatus according to the present invention;

FIG. 69 is an illustration showing an example of the data stored in thememory in the picture region dividing apparatus according to the presentinvention;

FIG. 70 is a graphical representation showing the principle of decidingthe luminance value in the picture region dividing method according tothe present invention;

FIG. 71 is an illustrations showing a picture communications systemusing the picture region dividing method according to the presentinvention;

FIG. 72 is a block diagram showing the construction of the picture coderapparatus using the picture region dividing method according to thepresent invention;

FIG. 73 is a block diagram showing the construction of a picturereproducing apparatus using the picture region dividing method accordingto the present invention;

FIG. 74 is a flowchart showing an algorithm of the picture regionboundary representing method according to the present invention;

FIG. 75 is a block diagram showing the construction of the pictureregion boundary representing method according to the present invention;

FIG. 76 is an illustration showing mapping of points in a block havingthe region boundary in the picture region boundary representing methodand apparatus according to the present invention;

FIG. 77 is an illustration for assistance in explaining the pointmapping in a block having no region boundary in the picture regionboundary representing method and apparatus according to the presentinvention;

FIG. 78 is an illustration for assistance in explaining the pointmapping in a block having a region boundary in the picture regionboundary representing method and apparatus according to the presentinvention;

FIG. 79 is an illustration for assistance in explaining an example ofhow to obtain a similar region in correspondence to each block in thepicture region boundary representing method and apparatus according tothe present invention;

FIG. 80 is an illustration for assistance in explaining another exampleof how to obtain a similar region in correspondence to each block in thepicture region boundary representing method and apparatus according tothe present invention;

FIG. 81 is a flowchart showing an algorithm of a region boundaryreproducing method for reproducing the region boundary represented bythe picture region boundary representing method and apparatus accordingto the present invention;

FIG. 82 is a block diagram showing a region boundary reproducingapparatus for reproducing the region boundary represented by the pictureregion boundary representing method and apparatus according to thepresent invention;

FIG. 83 is a flowchart showing another algorithm of a region boundaryreproducing method for reproducing the region boundary represented bythe picture region boundary representing method and apparatus accordingto the present invention;

FIGS. 84(a) to (c) are illustrations for assistance in explaining theprinciple of another algorithm of the region boundary reproducing methodfor reproducing the region boundary represented by the picture regionboundary representing method and apparatus according to the presentinvention;

FIG. 85 is an illustration showing an example of a radio communicationssystem using the picture region boundary representing method andapparatus according to the present invention; and

FIG. 86 is an illustration showing an example for realizing a picturesynthesizing tool by using the picture region boundary representingmethod and apparatus according to the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the attached drawings, some preferred embodiments ofthe method and apparatus for detecting a predetermined attribute of datasignals according to the present invention will be describedhereinbelow.

First Embodiment

FIG. 11 is a block diagram showing a first embodiment of the attributedetecting apparatus. In FIG. 11, first input code data 18 are given. Theinput code data 18 are codes indicative of various information such as aposition and a size of a similar region corresponding to each block,signal (pixel) arrangements, and a signal (pixel) value transformmethod, which are all formed by a fractal coder, for instance. Here, theoriginal data signals (code data) 18 are one-dimensional signals (audiosignals as shown in FIG. 12) or two-dimensional signals (video signal).In the case of the one-dimensional signal, the signals are divided intoa plurality of blocks in the time-axis direction as shown by dot linesin FIG. 12. Further, in the case of the two-dimensional signals, thesignals are divided into a plurality of blocks in a spatial direction.Further, the similar regions corresponding to the respective blocks aredesignated by codes 18.

The codes 18 are inputted to a mapping section 19. In this mappingsection 19, first an initial point is set to an attribute detectionposition. After that, it is discriminated which block the initial pointbelongs to, and a point (a mapped point) is mapped from the block to thesimilar region. The position data 13 indicative of the mapped pointoutputted by the mapping section 19 are stored in a memory 14temporarily. Thus, the first mapping has been completed.

In the second mapping, the position data 15 are read out of the memory14, and then the mapping is executed in the same way as the firstmapping. Further, the position data 13 of the second mapped point arestored in the memory 14. The mapping as described above are repeatedseveral to several tens times.

The position data 13 of the mapped point 13 are transmitted in sequenceto the attribute decide section 16. The attribute decide section 16detects whether the mapped point converges to one point or not; if sowhich point the mapped point converges; or whether it converges to aperiodic track; if so which periodic track converges; or whether itmoves in a chaos state; if so which region and along which track themapped point moves, etc. On the basis of the detected results, theattribute decide section decides the attribute at the attributedetection point, and further outputs the decided attribute data 17 tothe outside.

Here, the attributes are for instance such that (a) the dispersion ofthe reproduced values of data signals; (b) the dispersion of the datasignals; (c) the signal pattern period of the data signal; (d) thepresence or absence of abrupt changes of the data signals; (e) the sortof the data signals when classified into several portions according tothe signal patterns; etc. Further, the portion at which the data signalschange abruptly, the similar region is located at a relatively remoteposition in the data signals. Therefore, since the mapped points movewithin a wide range, when the mapped points go and return within a widerange conversely, it is possible to decide that a position at which thesignal changes abruptly exists in the vicinity of the initial point.Further, when the mapped points move periodically, it is presumed thatthe signals have a periodic pattern. Further, when the mapped points goand return only within a range, it is presumed that the similar signalpattern continues within the range.

With reference to FIGS. 13 to 15, the feature of mapping by use of thefractal codes will be described hereinbelow. FIG. 13 shows an inputpicture, in which there are four region of a star R₁, a triangle R₂, asquare R₃ and a background R₄. In FIGS. 13 to 15, each image of theregions R₁, R₂, R₃ and R₄ is described simply by segments, in practicehowever, these images can be represented by grayscale images. Since thepixel values or the textures are different from each other at therespective regions R₁, R₂, R₃ and R₄, it is assumed that at least when aman sees these images, these images can be recognized separately.Further, a point decided by the fractal codes, that is, the data of thesimilar region for each block is denoted by P.

Here, FIG. 14(a) shows a new picture prepared, in which initial pointsare arranged at random. Then, when the mapping P is repeated for all theinitial points shown in FIG. 14 (a), a difference in point arrangementdensity appears as shown in FIG. 14(b). Further, when the mapping isrepeated, the points are gathered as shown in FIG. 14 (c), in which fourclusters (point group) B₅, B₆, B₇ and B₈ can be formed by way ofexample.

The feature of the mapping of the present invention is that theseclusters B₅, B₆, B₇ and B₈ correspond to the regions R₁, R₂, R₃ and R₄,respectively. For instance, when only the cluster B caused by theinitial points as shown in FIG. 14(a) are left (by deleting all theother points), a star-shaped region appears as shown in FIG. 15. In thesame way, the cluster B₇ corresponds to the region R₂ ; the cluster B₈corresponds to the region R₃ ; and the cluster B₅ corresponds to theregion R₄ (background). Even if it is difficult to divide the region inthe state shown in FIG. 13, when the points are arranged being far awayfrom each other as shown in FIG. 14(c), the clustering can be madeeasily, so that the regions can be divided easily on the basis of theabove-mentioned clustering.

FIG. 16 shows a flowchart showing the procedure for deciding the regionto which the attribute detection position belongs, on the basis of themovement of the mapped points, by best use of the above-mentionedmapping feature.

The control flows are all executed by a control section (referred to ascontrol simply, hereinafter) including a CPU, ROM, RAM, etc. inaccordance with software.

In step S10, control substitutes an attribute detection position vectorx₀ for a position vector x in a picture. Further, in step S11, controlsubstitutes zero for the number of mappings n. In step S12, controlobtains the mapped point of x, and updates x. At the same time, in stepS13, control substitutes n+1 for n. In step S14, control checks whetherthe number n of mappings reaches a predetermined number N. If no,control returns to step S12. If yes, in step S15, control decides x₀ onthe basis of predetermined discrimination condition using x. Thediscrimination condition executed in step S15 is for instance such that[whether x belongs to a set 9 (shown in FIG. 14(c)]. If yes, controldecides that [x₀ belongs to a region 1]; and if no, control decides that[x₀ does not belong to a region 1].

Further, although being different from the region division, when thereproduced values of video signals are obtained as the attribute (aswith the case of the third embodiment, described later), since x is athree-dimensional vector (picture plane and pixel value), a pixel valueis also mapped in addition to the position value as the mapping P. Inthis case, the discrimination condition executed in step S15 is suchthat [whether a pixel value at x lies within a predetermined range]. Ifyes, the decision is such that [the reproduced value at x₀ is aninitially set pixel value]. If no, decision is such that [the reproducedvalue at x₀ is not an initially set pixel value].

In general, two outputs of [x₀ is a] and [x₀ is not a] are obtainedaccording to yes and no determined as an answer to the discriminationcondition.

FIG. 17 shows a flowchart showing another procedure for deciding theregion belonging to the attribute detection position. FIG. 17 isdifferent from FIG. 16 in that whenever x is replaced with P(x), in stepS16 control executes the discrimination processing. Here, if yes,control immediately decides [x₀ is a]. If no, in step S17, controlchecks whether the number n of mappings reaches N. If yes, controldecides [x₀ is not a]. If no, control returns to step S12.

Second Embodiment

FIG. 18 is a diagram showing a second embodiment, which is differentfrom the first embodiment in that the attribute decide section 16 shownin FIG. 11 is replaced with a period detect section 25. This perioddetect section 25 detects whether the data signals are periodic or not.The position data 13 of the mapped point obtained after several mappingsare stored in a memory 21. The mapping is further kept continued.Whenever mapping is executed, the position data 22 of the mapped pointstored in the memory 21 and the current position data 13 of the mappedpoint are both inputted to a difference section 23. The differencesection 23 detects a difference 24 between the two, and transmits thedetected difference 24 to the period detect section 25. When thedifference 24 is below a predetermined value, the period detect section25 decides that the data signals are periodic and therefore the track isclosed. In contrast with this, when the difference 24 is not reducedless than a predetermined value after the mappings are repeated severaltimes, the period detect section 25 decides that the data signals arenot periodic. That is, the periodic detect section 25 outputs theattribute data 26 indicative of periodic or non-periodic. Further, whenthe number of mappings and the track routes are checked until the trackis closed, it is possible to execute more diversified classifications.

Third Embodiment

FIG. 19 is a block diagram showing a third embodiment of the presentinvention, in which the feature of the present invention is applied tothe decoder. The picture is divided into square blocks as shown in FIG.1.

The codes 18 are codes indicative of various information such as thepositions and the sizes of similar regions corresponding to each block,pixel arrangements, and pixel value transform methods, which are allformed by a fractal coder, for instance. The codes 18 are inputted to amapping section 19. A pixel value decide section 31 transmits initialpoint data (composed of three components in total (two positioncomponents in a picture, and a pixel value component) to a selector 33.The position components of the initial point data 32 are positioncoordinates of a pixel required to be reproduced, and the pixel valuecomponent is a pixel value determined temporarily. The initial pixelvalue is switched later in the method of trial and error.

The selector 33 selects one of the two input signals and outputs theselected one signal. At this time, the selector 33 is so previously setas to output the initial point data 32. Therefore, the initial pointdata 32 are stored in a memory 14 as they are. After that, the initialpoint data are read from the memory 14 as the position data 34 of themapped point, and then inputted to a mapping section 19.

The mapping section 19 obtains a block 102 (as shown in FIG. 20) towhich the mapped point 101 belongs. The mapped point 101 is mapped to amapping point 104 on the basis of the codes 18 indicative of data of thesimilar region 103 corresponding to the block 102. In practice, themapping section 19 calculates the position coordinates of the mappingpoint 104 on the basis of data at the mapped point 101 and the similarregion 103. This calculation is a reversal transform (pixel sampling) asexplained under the description related to prior art with reference toFIG. 2. The mapped point 104 is not mapped onto the pixel position ingeneral, the coordinates are obtained as they are. At the same time, thepixel value at the mapped point 101 is transformed in the direction fromthe block to the similar region, to obtain a pixel value at the mappedpoint 104.

In more detail, when the pixel value is denoted by v and when thetransform coefficients are denoted by a and b, if the transform g(v) ofthe pixel value from the similar region 103 to the block 102 can beexpressed as

    g(v)=a·v+b

the mapping section 12 calculates the pixel value at the mapped point104 by the revere transform h of g as

    h(v)=(v-b)/a

where a and b differ according to the block.

With reference to FIG. 19 again, the mapping section 19 transmits theposition data 13 at the mapped point 104 to the select section 33. Theselect section 33 is previously so switched as to output the positiondata 13 at the mapped point 104. Therefore, the position data 13 areinputted and stored in the memory 14. After that, the position data atthe preceding mapping point are read from the memory 14 as the positiondata at a new mapped point. The similar mappings are repeated in thesame way.

In more detail, as shown in FIG. 21, now the mapped point 104 obtainedat the preceding mapping is used as a new mapped point, and a block 105to which the new mapped point belongs is obtained. Further, a mapping isexecuted from this block 105 to a similar region, so that a new mappedpoint 106 can be obtained. The pixel value at the new mapped point 106is also calculated. The above-mentioned mapping procedure is repeatedseveral times.

FIG. 22 shows changes of the pixel values at the mapped points obtainedwhen the mapping are repeated, in which the pixel values at the initialpoint are set to various values. In FIG. 22 the abscissa indicates thenumber of mappings and the ordinates indicates the pixel value at themapped points. Further, the original pixel values on the originalpicture range from "0" to "255".

The case where the pixel value at the initial point (i.e., the number ofmappings is zero) matches the reproduced value is shown by a thick line.As already explained under the description of the prior art, thereproduced picture A will not change according to the transform F.Therefore, this indicates that when a point just existing on thereproduced picture A is determined as an initial point, even if themapping is executed by tracing the transform F for each pixel in thereverse direction, as with the case of the present invention, it can beunderstood that the mapped point exists on A. Therefore, in thisembodiment, even if the mappings are repeated, since the mapped pointsexist on A in sequence, the pixel values will diverse, with the resultthat the pixel values lie between "0" and "255".

However, in the decoder, since the reproduced value at the initial pointis of course not known, the temporal pixel value at the initial point isdifferent from the reproduced value. In FIG. 22, the case where thepixel values at the initial point are different from the reproducedvalues are shown by thin lines.

Here, when a difference between the temporal pixel value at the initialpoint and the reproduced value is denoted by e₀, and the a differencebetween the pixel values at the mapped point and the reproduced value isdenoted by e_(i) (i=1, 2, 3, . . . ), the following relationship can beobtained

    e.sub.k =|1/ak|·e.sub.k -1(k=1, 2, 3, . . . )

where ak denotes a coefficient a of the pixel value transform h(v) usedat k. Since the coefficient a is determined less than one almost allcases so that the transform F is determined as the reduction transform,the reciprocal number of one is more than one. Therefore, e_(i)increases in accordance with an exponential function, so that the pixelvalue at the mapped points diverse. Further, when ak is positive, sincethe magnitude relationship between the reproduced value and the pixelvalue at the mapped point is not reversed due to mapping, when theinitial value is larger than the reproduced value, the pixel value atthe mapped point diverges in a positive direction. On the other hand,when smaller than the reproduced value, the pixel values at the mappedpoint diverges in a negative direction. Therefore, when an initial valueboundary between that diverging in a negative direction and thatdiverging in a positive direction is found by switching the initialpixel values in various ways, it is possible to find out the reproducedvalue. Further, when ak is a negative value, since the magnituderelationship between the reproduced value and the pixel value at themapped point is reversed due to mapping, when the number of negativevalues ak developed at the past mapping is an even number, the pixelvalue at the mapped point becomes a large positive absolute value, andwhen an odd number, the pixel value at the mapped point becomes a largenegative absolute value.

In FIG. 19, the divergence of the mapping can be discriminated asfollows: the pixel value at the mapped point designated by the positiondata 13 at the mapped point (obtained by the mapping section 12) areinputted to two comparators 35 and 35. The comparator 35 compares thevalue "255" with the pixel value at the mapped point designated by theposition data 13, and transmits the comparison result 37 to a pixelvalue decide section 31. Further, at the same time, the comparator 36compares the value "0" with the pixel value at the mapped pointdesignated by the position data 13, and transmits the comparison result38 to the same pixel value decide section 31.

When the pixel value at the mapped point exceeds "255" due to therepeated mappings, the pixel value decide section 31 interrupts themapping. Further, when the number of negative values ak formed by therepeated mappings is zero or an even number, the pixel value at theinitial point 32 is determined smaller than the previous value toexecute the mapping again. However, when the number of negative valuesak is an odd number, the pixel value at the initial point 32 isdetermined larger. Further, when the pixel value at the mapped point issmaller than 0" and further when the number of negative values ak iszero or an even number, the pixel value at the initial point designatedby the initial point data 32 is determined larger than the previousvalue. However, when the number of negative values ak is an odd number,the pixel value at the initial point is determined smaller. As describedabove, the upper end and the lower end of an interval in which thereproduced value exists are narrowed gradually, so that a finalreproduced value can be obtained.

Further, when the pixel value stays between "0" and "225" after apredetermined number of mappings have been repeated, the initial valueat that time is determined as the reproduced value. Further, when theposition data reach the boundary of the block during the mappingprocess, any one of the blocks sandwiching the boundary can be selected.

Further, as described in Document 1: "Fractal Image Coding: A Review",A. E. Jacquin, Proceedings of the IEEE, VOL. 81, No.10, October, 1993,there exists the case where the similar regions are not definedaccording to the blocks and pixel values are directly coded. In case themapping proceeding reaches the block as described above, when the valuea is always positive, as far as the pixel value at the mapped point isalways larger than the value given to the block, it is possible todiscriminate that the initial value is larger than the reproduced value.In contrast with this, as far as the pixel value at the mapped point isalways smaller than the value given to the block, it is possible todiscriminate that the initial value is smaller than the reproducedvalue. Further, when the value a is always negative, the similaralgorithm can be adopted.

According to the present embodiment, the apparatus scale can be reducedto such an extent that the frame memory is not required, as comparedwith the prior art apparatus. Further, when only a part (e.g., 1/4 onupper left side) of the picture is required to be reproduced, since thereproduced values are obtained only for the pixels at this area of thepicture, it is possible to reduce the amount of calculations and therebyto improve the processing efficiency. Further, since only the necessaryportion of a picture can be reconstructed, it is also possible toshorten the time required for reconstruction.

FIG. 19A shows an image reconstructing method corresponding to theapparatus shown in FIG. 19, which is a flowchart for reconstructingpixel value at a position (x0, y0). In FIG. 19A, (x, y) denotecoordinates on a picture, and v denotes a pixel value. Further, an imageis assumed to have pixel values of 256 gradations from 0 to 255.

S20: 128 is substituted for v0, and 64 is substituted for Δv0,proceeding to step S21.

S21: (x0, y0) are substituted for (x, y), and v0 is substituted for v,proceeding to step S22.

S22: 0 is substituted for n, proceeding to step S23.

S23: (x, y) are updated to w(x, y), and v is update to h(v), proceedingto step S24.

Here, w denotes a mapping from a block belonging to a mapped point (x,y) a corresponding point in an affine region. Further, h denotes atransform of the above-mentioned pixel value.

S24: n is updated to n+1, proceeding to step S25.

S25: if v is larger than 255, proceeding to S28; and if not so,proceeding to S26.

S26: is v is smaller than 0, proceeding to S29; and if not so,proceeding to S27.

S27: if v is smaller than a previously determined N, proceeding to S23;and if not so, proceeding to S32.

S28: v0 is updated to v0-Δv0, proceeding to step S30.

S29: v0 is updated to v0+Δv0, proceeding to step S30.

S30: Δv0 is updated to Δv0/2, to step S31.

S31: if Δv0 is larger than a previously determined E, proceeding to S21;and if not so, proceeding to S32.

S32: a reconstructed value at (x0, y0) is decided as v0.

This algorithm checks the divergence state, on the assumption that thereconstructed value is first 128. Then, if v is larger than 255, apositive divergence is discriminated. At this stage; since it can beunderstood that the reconstructed value lies between 0 and 128,successively an intermediate value between 0 and 128 is checked. On theother hand, if v0 is 64 and further v is smaller than 0, a negativedivergence is discriminated. This indicates that the reconstructed valuelies between 64 and 128. As described above, the range where thereconstructed value lies is gradually narrowed, and stopped when therange becomes smaller than an allowable value E of the reconstructedvalue error. The value v0 at this stop time is determined as thereconstructed value. Further, when v still lies between 0 and 255 afterN-times mappings, v0 is discriminated as being sufficiently approximateto the reconstructed value, so that v0 at this time is determined as thereconstructed value.

Fourth Embodiment

FIG. 23 is a block diagram showing a fourth embodiment of the presentinvention, in which both forward and reverse transforms are used formapping. In the same way as with the case of the third embodiment, themapping section 19 executes the point mapping repeatedly on the basis ofthe codes 18. In this embodiment, however, the mapping section 19executes only the position mapping, without executing the pixel valuemapping. Therefore, only the pixel positions at which the reproducedvalues are required to obtain are stored in the memory 14, and afterthat only the mapped point positions are stored. Further, apredetermined number N of mappings are executed. The mapping section 12outputs block specify data 41 indicative of which block the mapped pointbelongs to are outputted in sequence. The N-units of the block specifydata 41 are stored in the memory 42. In the example of FIG. 21, theblock specify data 41 are stored in the order of block 102→block105→block 107. In this example, N is 3.

Then, a pixel value of "128" for instance is set to the memory 44.Further, the block specify data 43 written at the last are read from thememory 42, and further the pixel value transform in the direction fromthe corresponding similar region to the block is executed for the pixelvalue 45 read out of the memory 44. That is, the pixel value transformsection 46 obtains the pixel value 47 by calculating the followingexpression:

    g(v)=a·v+b

in accordance with the aforementioned-mentioned notation. Here, thevalues a and b are different from each other for each correspondingblock, and these values are read from the codes 18 by the pixel valuetransform section 46. The pixel value transforms are executed by N timesby reading the block specify data in sequence from the memory 44, andthe transformed results are outputted to the outside as the reproducedvalues 48.

The reason why the reproduced values can be obtained as described abovewill be explained hereinbelow. In the example shown in FIG. 21, theerror at the initial point increases with increasing number of mappingsaccording to an exponential function. This indicates the following fact:when mappings are traced from the right to the left, even if the mappingstarts with an error on the right side, the error can be reducedgradually when traced gradually in the reverse direction (from the rightside to the left side), and roughly approaches the reproduced valueshortly. However, when the mappings are traced in the reverse direction,since it is necessary that the point is mapped at any desired pixelpoint just after the N-th mapping, it becomes necessary to previouslystore the position mappings in the memory 42 and then to read them insequence in the reverse direction. At this time, since the pixel valuetransform is decided for each block, it is unnecessary any detailed datarelated to the pixel positions. That is, data indicative of which blockthe pixel belongs to are sufficient. Here, the error eN at the N-th timemapping can be expressed as

    eN=e.sub.0 /|a1·a2 . . . aN|

where ak (k=1, 2, . . . N) denotes a coefficient a of the k-th timemapping.

Here, since the pixel values of the reproduced picture are between "0"and "225", when the error of the reproduced value is required to besuppressed equal to or less than E, if N is determined to satisfy thefollowing expression:

    E/|a1·a2 . . . aN|>225

it is possible to securely suppress the error less than E, even if thepixel value 45 starts from any value between "0" and "225". Forinstance, if

    a1=a2=. . . =aN=1/2E=1

N is determined to be 8 or more.

In the case of the fourth embodiment, although the capacity of thememory slightly increases, as compared with the third embodiment, sinceit is unnecessary to check the divergent status in the method of trialand error, the quantity of calculations can be reduced.

The second aspect of the present invention will be explainedhereinbelow.

Fifth Embodiment

FIG. 24 is a block diagram showing a fifth embodiment of the presentinvention. In FIG. 24, codes 51 indicative of the position transformdata are inputted from the outside and then stored in a positiontransform memory 52. The position transform code 53 read from theposition transform code memory 52 are transmitted to an edge detectsection 54. In the edge detect section 54, a contour (i.e., edgepositions) of an object in a picture are detected, and the detected edgeposition data 55 are transmitted to an edge image form section 56. Theedge image form section 56 forms an edge image 57 by distinguishing animage on the basis of the luminance value or color (e.g., an edgeportion designated by the edge position data 55 is determined as blackand the remaining portion is determined as white), and outputs theformed edge image 57 to the outside.

Sixth Embodiment

FIG. 25 is a sixth embodiment in which the fifth embodiment (shown inFIG. 24) is realized in another way. That is, the edge detect section 54shown in FIG. 24 is realized by a fixed point detect section 58. Thefixed point detect section 58 obtains the fixed point position (at whichthe position is transformed) for each block. The obtained fixed pointposition data 59 are transmitted to the edge image form section 56. Theedge image form section 56 forms the point designated by the positiondata 59 at the fixed point and the edge image 57 (a group of dots inthis embodiment) distinguished by other different factors (e.g., color,luminance value). The formed edge image 57 is outputted to the outside.

Now, as shown in FIG. 26, the assumption is made that in the picture 201having an edge 202, a region 204 has been determined as a similar regionin the block 203. In the same way, as shown in FIG. 27, the assumptionis made that a region 206 has been determined as a similar region in theblock 205. Further, FIG. 28 shows a fixed point 207 for the similaritytransform in the block 203, and FIG. 29 shows a fixed point 208 for thesimilarity transform in the block 205. As shown above, since the fixedpoints 207 and 208 are on the edge 202, when these fixed points areobtained for each block and then expressed on the picture, it ispossible to recognize an external shape of an object.

Seventh Embodiment

FIG. 30 is a block diagram showing a seventh embodiment, in which afixed point connect section 60 is interposed between the fixed pointdetect section 58 and the edge image form section 56. Therefore, in thisembodiment, line data obtained by connecting the fixed points aretransmitted to the edge image form section 56, instead of the pointdata. The fixed point connect section 60 connects the fixed points whichseem to be located on the same edge (e.g., a fixed point 207 of theblock 203 shown in FIG. 28 and a fixed point 208 of the block 205(adjoining to the block 203 ) shown in FIG. 29), without connecting allthe fixed points to each other.

Further, being slightly different from the above-mentioned example, whenthe fixed points 211 and 210 of the two adjacent blocks 203 and 205 arelocated far away from each other as shown in FIG. 32, only the segment213 shown by a solid line in the two blocks 203 and 205 is determined asan edge. This is because there exists the case where although the linebetween the points 210 and 211 is overlapped with the edge in and aroundthe blocks 203 and 205 or regions 204 and 206, the line is dislocatedfar away from the edge.

Eighth Embodiment

FIG. 33 is a block diagram showing an eighth embodiment, in which thefixed point detect section 58 shown in FIG. 25 is shown in morepractical way. That is, the position transform is expressed by affinetransform w as follows: ##EQU3## where x, y denote the abscissa of thepixels and the ordinate value; and a, b, c, d, e, and f are all affinetransform coefficients. Further, if ##EQU4##

The expression (1) can be expressed as

    X'=AX+b                                                    (2)

where X' denotes the point at which the X is transformed.

In FIG. 33, a transform coefficient decide section 61 decides A and B(i.e., a to f). For this purpose, first the following three points X₁(=(X₁, Y.sub.)), X₂, and X₃ are set, for instance on the upper leftside, the upper right side, and the lower left side, respectively. Thesethree point are position-transformed to obtain X₁ ', X₂ ', and X₃ '.Since these values satisfy the expression (2), the followingsimultaneous equations can be obtained

    X.sub.1 '=AX.sub.1 +b

    X.sub.2 '=AX.sub.2 +b

    X.sub.3 '=AX.sub.3 +b

Since these simultaneous equations are six linear simultaneousequations, it is possible to obtain six un-known quantities. Thetransform coefficient decide section 61 transmits the six values a to f(62 ) thus obtained to a fixed point decide section 63.

In the fixed point decide section 63 solves the two-element linearsimultaneous equations as follows:

    X.sub.0 =AX.sub.0 +b

to obtain the fixed point 59 of X₀ =(x₀, y₀).

Ninth Embodiment

An embodiment for obtaining an edge by use of flow vectors will bedescribed hereinbelow. As shown in FIG. 34, the flow vectors 220indicate which direction the respective points in the similar region aretransformed. In practice, the transform points are obtained at eachpoint, and a gradient of a line obtained by connecting two pointscorresponding to before and after transforms is determined as a flowvector. Here, the magnitude of the vector is previously determined.

FIG. 35 shows a flow vector 221 indicative of the position transform ofthe block 205. Further, FIG. 34 corresponds to the already-explainedexample shown in FIG. 26, and FIG. 35 corresponds to thealready-explained example shown in FIG. 27, respectively. Further, whenthe edge 231 is curved as shown in FIG. 36, in general, a revolutiontransform is added to the position transform of the similaritytransform. In this example, the region 230 is transformed clockwise tothe block 231. FIG. 37 shows the flow vector 232 of this case shown inFIG. 36. These flow vectors 220 and 221, 222 and 232 have such naturethat the directions thereof are the same as the respective edgedirections at the edge portions. In an example as shown in FIG. 38, whentwo flow vectors 220 and 221 are overlapped with each other at the edgeportion, the directions of the two vectors match each other. Therefore,the position at which an absolute value of an inner product of twovectors exceeds a predetermined value can be decided as an edge.

FIG. 39 is a block diagram showing an embodiment for obtaining an edgeby use of the flow vectors. A flow vector detect section 71 detects flowvectors 72. A direction comparator 73 calculates an absolute value of aninner product of the flow vectors 72 to detect an edge 74.

Further, the ninth embodiment has been explained by taking the case onlythe similarity transform of two blocks, on the basis of the two examplesas shown in FIGS. 26 and 27. However, when the number of the blocks isincreased, it is possible to detect an edge in a wider range.

Tenth Embodiment

FIG. 40 shows an embodiment in which position transform codes aregenerated on the basis of random numbers. In this embodiment, theposition transform codes 412 inputted to a position transform section404 are different from the prior art decoder shown in FIG. 5A. That is,the position transform codes 412 are set at random for each block by arandom number generate section 411. For instance, with respect to thepositions and sizes of the similar regions included in the positiontransform codes, a plurality of regions are previously set at random inthe same probability. For the rotation angle is also set at random inthe same way. When the position transform codes formed as describedabove are used, the shape of an object included in an original pictureis no more reproduced. However, since the pixel value transform codes408 of the original picture are given, it is possible to reproduce theratio of bright portion to the dark portion of the reproduced pictureand a rough bright-dark pattern. Therefore, it is possible to feel theimpression or the quality of the original picture in the reproducedpicture. In addition, since the position transform codes of the originalpicture are not required as the codes 402, it is possible to economizethe capacity to such an extent as to corresponding to the positiontransform codes, in the case of a data base for retrieval only. Further,the transmission quantity of codes can be reduced.

Eleventh Embodiment

FIG. 41 is a block diagram showing the eleventh embodiment, in which theposition transform codes 414 and the pixel value transform codes 413 areinputted to the position transform section 404 and the pixel valuetransform section 407, respectively of the prior art decoder shown inFIG. 5A. Here, the already-obtained picture codes 402 and signals 416inputted from a code input section 417 are both inputted to a code setsection 415. Further, the code input section 417 is provided with tenkeys, a mouse, a touch sensor, a pen, etc, for easy manipulation by anoperator.

In this eleventh embodiment, the reproduced picture can 405 can bechanged by changing a part of the codes 402, when the operator operatesthe code input section 417.

FIGS. 42 and 43 show examples in which position transform of the codes402 are changed. In the example shown in FIG. 42, a similar region 241and a block 240 are both given by codes 402. Although omitted forbrevity, other similar regions can be given to the other blocks. In thereproduced picture at this time, an object 242 can be reproduced in theshape as shown. Here, when the region 241 is rotated a little clockwisewith the point 243 as its center as shown in FIG. 43, the lower portionof the object 242 within the block 240 is a slightly elongated. In thesame way, the object within the block 244 can be deformed a littleslender.

As described above, when the position transform codes are changedgradually, the shape of an object can be changed slightly as shown inFIG. 44. Therefore, in this embodiment, it is possible to execute themorphing (deforming) processing such that the contour of a human facepicture, for instance can be modified gradually by changing the codelevel.

Further, FIGS. 45 and 46 show the case where the pixel value transformcodes are changed. When the addition and/or subtraction value of thepixel value is small, a relatively flat texture is obtained (e.g., ablue sky shown as the background in FIG. 45). Therefore, when theaddition and/or subtraction value is changed for each block, it ispossible to obtain a bright and dark texture (e.g., a cloudy sky asshown in FIG. 46). That is, it is possible to process the picture on thebasis of the code level.

FIGS. 47(a) to (c) show an example in which all the codes are inputtedto the code input section 417 without use of any codes 402 in FIG. 41.This is an example of an average value separation-type fractal coding(See "Image compression by iterative transform coding"; by Ida, Datake,5-th Circuit and System, Karuizawa, Workshop Paper Collection, April,1992). In this method, a block average value is used, instead of theaddition and/or subtraction value of the pixel value transform codes.FIG. 47(a) shows an example in which the luminance value is roughlydetermined for each block. FIG. 47(b) shows an example in which theposition transform is set in such a way that an egg-shaped edge can beformed. In this case, a region 252 is set for the block 251, forinstance, and further the other blocks in the same way. Further, FIG.47(c) shows an example in which a picture is formed by use of both thepixel value transform and the position transform set in FIGS. 47(a) and47(b), respectively. As described above, it is possible to form anydesired picture by giving rough luminance value distribution and theedge.

Twelfth Embodiment

FIG. 48 is a block diagram showing a twelfth embodiment, in which codesfo reproducing a picture into an enlarged shape can be obtained. In thisembodiment, the processing of the region picture data 305 and the blockpicture data 310 are different from the prior art decoder shown in FIG.4. The region picture data 305 are transmitted to a transform section321 as the original size, and then processed for rotation transform,reduction and addition and/or subtraction transform in the pixel valuedirection. The transformed region data 322 are inputted to thedifference section 311. On the other hand, a size enlarge section 323enlarges the block picture data 310 to obtain the size and the number ofpixels the same as those of the region. The obtained enlarged block data324 are stored in a memory 325. Further, a transform section 321transforms the region data 322. The transformed region data 322 areinputted to the difference section 311. The enlarged block data 326 readfrom the memory 325 and the region data 322 outputted from the transformsection 321 are both inputted to the difference section 311 at the sametiming. After that, the transform is executed in such a way that theerror 312 outputted from the difference section 311 can be minimized,and the codes are outputted in the same way as with the case of theprior art coder as shown in FIG. 4.

In the transform section 321, several transforms (e.g., four rotationtransforms in unit of 90 degrees) are executed in sequence to evaluatethe errors. In this case, however, when the size enlarge transform isexecuted for the same block for each sequential transform, the quantityof calculation increases. In this twelfth embodiment, therefore, thedata obtained by a size enlarge section 323 are stored in the memory325, and the data for the same block are read repeatedly to reduce thequantity of calculations. Further, when the calculation quantity is notimportant, the memory 325 can be omitted.

As described above, in the second aspect of the present invention, it ispossible to form a simple picture on the basis of simple codes, so thatpictures can be processed on the basis of the code levels.

A third aspect of the present invention will be described hereinbelow,in which the feature pattern size can be detected.

Thirteenth Embodiment

FIG. 49 is a block diagram showing an apparatus for detecting the sizeof the feature pattern of signals. The size detector is composed ofstorage means 20, scale setting means 27, measurement detecting means28, and specific size deciding means 29. The function of the sizedetector will be described hereinbelow with reference to a flowchartshown in FIG. 50. First, input signals are stored in the storage means20. According to the input signals stored therein, a plurality of scalesare set by the scale setting means 27. On the basis of the scale thusset, a measure B is detected by the measure detecting means 38 to obtainthe fractal dimensions related to the input signals (in step F1 shown inFIG. 50). In the case of a signal curve g as shown in FIG. 51A, forinstance, the measure B can be obtained by covering the signal curve gwith a plurality of cubes having one side of scale ε and by counting thenumber of cubes. This measure detecting method is disclosed, forinstance by B. B. Chaudhuri, N. Sarkar, P. Kunde; "Improved fractalgeometry based texture segmentation technique" IEE Proceedings-E, vol.140, No.5, September, 1993.

The measure detection as described above is executed on the basis of theseveral scales ε_(i) (i=0, 1, . . . ) set by the scale setting means 27.The specific size deciding means 29 detects the change rate (Δ log B)according to the scales ε of these measures (log B) (in step F2 in FIG.50). The specific size deciding means 29 discriminates whether thechange rate of the measures satisfies a predetermined condition or not.If satisfied, that is, if the change rate of the measures exceeds apredetermined value, the specific size deciding means 29 determines thescale ε_(T) at this time as a specific size, and outputs the determinedscale to the outside (in step F3 in FIG. 50). Further, when the measureshave been obtained in all the scales previously prepared, control endsthe specific size detection. When the measures have been not yetobtained in all the scales, control changes the scale and repeats thesame processing (in steps F4 and F5 in FIG. 50).

In this embodiment, a plurality of cubes are used to detect the measure.Without being limited thereto, however, in the case of theone-dimensional signal such as audio signals, a segment having a lengthε can be used as the scale. Further, when the audio signals are takeninto account as two dimensions of amplitude and time, the measure can beobtained by use of square areas as the scale. Therefore, the measure canbe decided according to the feature pattern of the signals to bedetected.

In the case of video signals, it is possible to use square areas for thetwo dimensional signals or cubic volumes for three dimensional signals(including the luminance value direction) as the scales. Further, thedynamic ranges and the logarithm of the signals for the scales can beused. Further, as a simplified method, it is also possible to use thenumber of signals which change within the square scale. Further, theprior art blanket-covering technique and the fractal dimension decidingtechnique can be also used. As the algorithm for measuring the measures,it is possible to use figures having the same dimension as the generaldimension of the signals.

When the signal measures are measured in the set scale, the scales canbe cut off being overlapped with each other or the measures can bemeasured by overlapping the scales little by little. When overlapped,the measures are obtained by averaging the measures by use of the numberof overlappings. In this case, the measure can be measured by all thepossible cutting methods or at random. Further, another rule can beadopted for measurement. FIG. 51B shows the relationship between themeasure change rate and the scale size.

Further, the change of the measures according to the scale can bedecided on the basis of whether the change rate of the measure ispositive or negative or by use of the difference and dispersion ofabsolute values of the change rates.

In the above-mentioned embodiment, the measures are obtained for aplurality of scales, and the specific size (the size of the signalfeature pattern) has been detected on the basis of whether the changerate of these measures can satisfy a predetermined condition or not.Here, this detecting principle will be explained hereinbelow.

Here, the assumption is made that the measure detecting means 28 isprovided with a signal pattern as shown in FIG. 52(a). When the scale issmall, this change can be obtained by use of a blanket as expressed inFIGS. 52 (b) and 52(c) However, when the scale ε_(T) exceeds apredetermined value, since the upper blanket surface and the lowerblanket surface are both flattened, the change pattern of the signalsare buried in the blanket. This can be expressed as shown in FIG. 53(when expressed in the same way as shown in FIG. 5B). In the prior artfractal dimension, these changes are approximated by use of a straightline. In practice, however, ε_(T) can be observed as a broken line. Inother words, when the change rate of the measures is broken at a certainscale as shown in FIG. 53, since the change rate can be observed as abroken graph, it is possible to detect the pattern size of the signalfeature pattern by detecting the scale ε_(T) at which the change rate isbroken.

As described above, according to the present invention, being differentfrom the prior art technique, since it is unnecessary to divide theblocks and the regions, it is possible to easily detect the size of thesignal feature pattern.

When the detecting apparatus as described above is used for the videosignals, a distance between an end of a picture and a desired region canbe detected as a specific size. This is because the measures can beobtained in the same way as when there exists a large change of thevideo signal on an end of the picture, as shown in FIGS. 54(a) and54(b). Further, conversely, when the measure is obtained by turning upthe end of the picture by setting the size of the given picture to thescale, since there exists no change in the video signal at the end ofthe picture, the distance from the end of the picture cannot bemeasured, so that another distance between both ends of the region inthe picture can be detected. FIGS. 54(a) and 54(b) show the pictureposition on the abscissa and the luminance value of the video signal onthe ordinate. Further, in FIG. 54(a), since a specific size d isdetected on the assumption that the luminance value is zero within apicture position 0<x<x1, the measures are detected as that the regionschanges at the positions x=x1, x2, x3 and x4, respectively. By doingthis, d2 and d3 are detected as specific sizes. On the other hand, inFIG. 54(b), since the measures are detected by turning up the luminancevalue at the positions x=x2 and x4, the distance from an end of thepicture cannot be detected, with the result that only the distance d1 ofa specific region in the picture can be detected.

Here, an example in which the present embodiment is applied to divide apicture having mixed textures will be explained, with reference to FIGS.55(a) and 55(b). In this example, the textures are divided. As shown inFIG. 51A, a cube having one side scale ε is considered for all thepossible scales. The luminance surface of the stored texture picture iscovered by the minimum possible number of cubes. This number isdetermined as the measure B(ε) for the scale. Further, the change rate(gradient) of the measures decreasing in proportion to the scale isobserved to obtain the specific scale as the feature rate. In thisexample, the specific scales εT₁ and εT₂ represent the distance d₁ andd₂ between the picture end and the change points of the textures.Therefore, the textures can be easily separated by these distances.Further, as shown in FIG. 55(b), it is possible to know the complicatednature of the switched textures on the basis of the gradient of themeasure change to εT₁ (fractal dimension), the gradient from εT₁ to εT₂and the gradient from εT₂ and after.

FIGS. 56(a) and (b) shows an example to which the present embodiment isapplied to know the size and the position of any desired region having afeature pattern. In this example, the size and the position of theregion are obtained. For instance, as shown in FIG. 56(b), when themeasures are obtained in the same way as with the case of the example ofthe above-mentioned texture division, the specific scales ε₁, ε₂, ε₃ andε₄ of the N×N pixel size can be obtained. When the end of the picture isnot turned up, these specific scales correspond to d₁, d₂, d₃ and d₄.There are some methods of knowing the corresponding relationship betweentwo of them. For instance, in the case of the example shown in FIGS.57(a) to 57(f), all the regions (hatched portions) of the all possiblesizes decided by the obtained scales ε₁, ε₂, ε₃ and ε₄ are assumed, andthe picture is partitioned by ε₁ and further the specific scales of theremaining regions are detected again. Further, the correct positions canbe decided by checking whether there exists any contradiction when thespecific scales obtained as a result of re-detection are assumed. Inthis example, since the scales ε₂, ε₃ -ε₁, and ε₄ can be detected inFIGS. 57(a), 57(b), 57(c) and 57(d), ε₁ =d₁ is determined to be correct.In the same way as above, the pictures as shown in FIGS. 57(a), 57(b),57(c) and 57(d) are discriminated by the region partitioned by ε₂. Byrepeating the above-mentioned discrimination, it is possible to obtainthe correspondence between the specific sizes and the actual distances.

In the example for obtaining the above-mentioned region positions, whenthe method of turning up the end of the picture is used together, sincethe region sizes r1 and 2 (as shown in FIG. 56(a)) can be detecteddirectly, the region positions can be specified more easily. Forinstance, there exists such a method of deciding the horizontal andvertical specific sizes separately, by fixing one side of the region byone of the two specific sizes and by measuring again the measure in unitof rectangle whose scale corresponds to the other side of the region.

As another method of detecting the sizes of any desired region, it ispossible to use the method of obtaining the measures by use of arectangle having a scale of g₁ (vertical) and g₂ (horizontal). When themeasures are obtained by use of a rectangle having the same sizes asthose of the region, the change rate changes abruptly, so that a set oftwo sides of the rectangle at this time are determined as the specificscales. In addition to the rectangle, a triangle, circle, anythree-dimensional figures can be used where necessary.

When various patterns are mixed in the signals as described above, asfar as there exists one size appearing often, this size can be detectedon the basis of the change rate of the measures used as the specificscale. For instance, this is effective when the character size isdetected on the basis of the character region. As the pre-processing ofthe character recognition, when the character region position isdetected roughly by scanning the vertical and horizontal pixel values(projection) and after that when the detailed characters are detected inaccordance with the present invention, it is possible to easilypartition the characters accurately. Further, it is possible to use theregion division technique according to the present invention for theposition detection of character regions by projection. Further, asanother application, it is also possible to detect the characterthickness on the basis of the character picture.

Fourteenth Embodiment

FIG. 58 is a block diagram showing a fourteenth embodiment of thefeature pattern size detecting apparatus according to the presentinvention. This embodiment is different from the thirteenth embodimentshown in FIG. 49 in that discriminating means 30 is newly provided. Thisembodiment is effective when the input signals are video signals. On thebasis of the specific sizes outputted by the specific size decidingmeans 29, the discriminating means 30 discriminates the number ofspecific sizes, whether the specific size satisfies a predeterminedcondition, or whether the picture block is further divided or not.

Here, if the re-division is decided, a division command of the videosignals stored in the discriminating means 30 is given to the storagemeans 20. If re-division is not decided, the specific sizes areoutputted and used to specify the edges of a picture divided intoblocks. The given conditions are for instance such that whether an edgecan be specified, whether an edge in a desired range can be specified,etc. which are determined according to the desired feature pattern,respectively.

FIG. 59(a) to 59(c) show an example in which the present embodiment isapplied to the region division of video signals. In FIGS. 59(a) to59(c), the distances from the end of the picture are determined as thespecific sizes. Two larger measure change rates (Δlog B as shown in FIG.51B) are sued as the specific sizes. First, as shown in FIG. 59(a), thespecific sizes are obtained for the whole picture, and the block isdivided by use of the two larger scales (ε₁, ε₂) (e.g., as with theexample of detecting the region position) The specific sized areextracted again for the re-divided block as shown in FIG. 59(b). Theabove-mentioned procedure is repeated, until the edge can be specifiedas shown in FIG. 59(c). By doing this, it is possible to specify theboundary of the region included in the block in further detail. Inaddition, it is also possible to divide the region in accordance withthe method of detecting the size and the position of the region, asexplained with reference to FIGS. 57(a) to 57(f). Further, as with theexample shown in FIGS. 55(a) and 55(b), it is possible to know thecomplication degree of the divided region on the basis of the changerate of the measures obtained before and after the specific sizes arechanged.

In the above-mentioned examples, it is possible to use another simpledividing method previously determined for the re-division of the block.Further, when there exist some previous region data, any desiredspecific size can be selected from a plurality of specific sizes.

Further, the fourteenth embodiment is of course provided with the effectsimilar to that of the thirteen embodiment.

Here, the other preferred embodiments of the third aspect of the methodand apparatus for dividing the picture region will be describedhereinbelow in detail with reference to the attached drawings.

Prior to the description of the practical embodiments, the basic conceptof this third aspect of the present invention will be explained withreference to the flowchart shown in FIG. 60.

In step ST1, control divides one picture into a plurality of blocks, andmappings are obtained for the respective similar regions correspondingto the respective blocks (fractal coding step).

In step ST2, a plurality of mapping points a_(n) (n=1, . . . , N) areobtained by repeating the transform N-times in accordance with anattribute, beginning from an initial point defined as a specific pointon the coordinates on the basis of a predetermined attribute (mappingpoint deciding step). Here, the attribute implies a pixel position orluminance value, for instance. Further, the specific point on thecoordinates indicates a point within an X-Y-Z space, when the positionsare determined on an X-Y plane and the luminance value is determined onthe Z axis.

In step ST3, a region corresponding to a plurality of the blocks havingthe respective points a_(m) (m=0, . . . , N-1) transformed at aplurality of the mapping points a_(n) (n=1, . . . , N) is obtained asmapping (mapping discriminating step). This step ST3 are repeated untilall the mapping points are decided (in step ST2), and the mappingdecisions end.

In step ST4, the contents of the predetermined attributes at the initialpoint an are obtained by use of at least two mapping points of aplurality of mapping points a_(n) (n=1, . . . , N) (attribute contentdeciding step).

In step ST5, the region corresponding to the mapping is divided as thespecific feature regions on the picture, in accordance with thepredetermined attributes obtained in the attribute content deciding step(feature region dividing step).

The procedure of obtaining the mapping points by use of the mappingpoint deciding step and the mapping point discriminating step will beexplained hereinbelow with reference to FIGS. 61(a) to 61(c).

An initial point a₀ is included in a block in FIG. 61(a). Further, amapping to a similar block obtained in accordance with the fractalcoding step is allowed to correspond to this block. Therefore, a mappingcorresponding to the pixel point included in the block can be known bythis mapping, so that the initial point a₀ is transformed to the mappedpoint a₁ by this mapping (mapping point deciding step).

Then, in FIG. 61(b), the transformed mapping point a₁ is included inanother block again. A mapping to a similar block is allowed tocorrespond to this block in the same way as with the case shown in FIG.61(a). In the mapping discriminating step, a block having the mappingpoint a₁ is obtained on the basis of the position of the mapping pointa₁, to discriminate the corresponding mapping. This mapping point a₁ istransformed again to another mapping point a₂ in the mapping pointdeciding step.

FIG. 61(c) shows the attribute content deciding step. By repeating theabove-mentioned steps N-times, the mapping points a₀ to a_(N) areobtained to obtain the mapping track. For instance, a track of themapping points obtained beginning from one initial point is enclosed bya range A, B and C, respectively, and each of these regions is decidedas an attribute content deciding region.

FIG. 61A is a block diagram showing an image segmenting apparatusaccording to the present invention. In FIG. 61A, coordinates 612 at amapped point stored in storing means 611 and mapping parameters 614obtained on the basis of a given mapped point 613 are inputted totransforming means 615. The coordinates 616 at the mapped pointoutputted from the transforming means 615 are stored in the storingmeans 611. The coordinates 612 at the mapped point outputted from thestoring means 611 are inputted to attribute detecting means 617 toobtain a result 618 of attribute decision.

As shown in FIG. 69, an initial position of a set point and the positionof the mapped point position are both stored in the storing means 611.Therefore, the set point can be transformed by the transforming means615 on the basis of the mapping parameters 614 to realize the affinetransform defined at the set point, and then stored in the storing means611. The above-mentioned processing is reiterated N times. By use of theN-time mapped points 612 at all the points, the attribute detectingmeans 617 clusters the N-time mapped points corresponding to therespective set points. Being labeled by the cluster belonging to theN-time mapped points, the obtained label 618 is outputted as anattribute.

As the initial point for deciding the attribute content decidingregions, all the pixel points in the picture can be used. Or else, someof them can be used as the representative values.

FIG. 62(a) to 62(b) are illustrations for explaining the feature regiondividing step for dividing the feature regions on the basis of theattribute content deciding regions.

In FIG. 62(b), the regions a, b and c for deciding the attributecontents are decided. For instance, these regions are decided by use ofsome initial point as the representative points in the attribute contentdeciding step as explained in FIG. 61(c). The attributes of the initialpoints other than the representative points can be decided on the basisof the in which regions a, b, c, and d the respective N-time mappingpoints are included.

For instance, color is decided for each attribute in which N-timemapping points are included, and further when this color is displayed atthe initial point, as shown in FIG. 62(b), it is possible to color thefeature region included in the picture. In other words, when N-timemapping points are included in the region a in FIG. 62(a), the initialpoint lies in the region a shown in FIG. 62(b); and when N-time mappingpoints are included in the region b in FIG. 62(b), the initial pointlies in the region b shown in FIG. 62(b); and the same can be applied tothe regions c and d.

Therefore, since the attribute of the N-time mapping points can bedecided for each feature region in the picture, it is possible to dividethe feature regions by deciding the attribute of the N-time mappingpoints.

Fifteenth Embodiment

FIG. 63 is a flowchart for assistance in explaining the fifteenthembodiment, in which the procedure of the picture region dividing methodis shown.

Control first inputs all the pixel point coordinates in sequence (instep ST10). Then, control transforms the inputted pixel coordinates C13on the basis of the predetermined mapping data (in step ST11), andfurther discriminates whether the transformed coordinates C14 are usedfor the clustering point (in step ST12). The cluster point is referredto as a set point. Further, the attribute region decided by the setpoint is referred to as an attribute region. The point obtained afterthe points have been transformed n times (n=1, 2, . . . , N) is referredto as n-time mapped point. In step S12, if at the set point, controlinputs the coordinates C15 at the set point (in step ST13), to decidethe coordinates C16 of the attribute region by use of at least two ofthe n-time mapped points (n=1, . . . , N) Control discriminates whetherthe N-time (the number of settings) transforms have been executed (instep ST14), and outputs the coordinates C17 at the mapped point. Controldecides the attribute by labeling (classifying) the attribute regions,to which the N-time mapped points of the initial points belong, on thebasis of the coordinates C17 of the mapped points and the coordinatesC18 of the attribute region obtained in step ST13, and outputs thecoordinates C18 of the decided result (in step ST15). Finally, controldiscriminates whether the attributes have been obtained for all thepixels, completing the procedure (in step ST16).

FIG. 63A is a block diagram showing an image segmenting apparatusaccording to the present invention. In FIG. 63A, coordinates 636 at amapped point stored in storing means 635 and mapping parameters 632obtained on the basis of a given mapped point 631 are inputted totransforming means 633. The coordinates 634 at the mapped pointoutputted from the transforming means 633 are stored in the storingmeans 635. The coordinates 636 at the mapped point outputted from thestoring means 635 are inputted to second attribute storing means 637.The coordinates 636 at the mapped point outputted by first storing means635 and the coordinates 638 at the mapped point outputted by the secondstoring means 637 are inputted to attribute detecting means 639, toobtain a result 640 of attribute decision.

As shown in FIG. 69, an initial position of a set point and the positionof the mapped point are both stored in the first storing means 635.Therefore, the set point can be transformed by the transforming means633 on the basis of the mapping parameters 632 to realize the affinetransform defined at the set point, and then stored in the first andsecond storing means 635 and 637. The above-mentioned processing isreiterated N times. The positions of n-time (n=0, . . . , N-1) mappedpoints of the different reiterative number obtained midway during theN-time reiterative mappings of the set point are stored in the secondstoring means 637. By use of the N-time mapped points 636 at all thepoints and further the positions 638 of the n-time (n=0, . . . , N-1)mapped points, the attribute detecting means 635 clusters the mappedpoints corresponding to the respective set points. Being labeled by thecluster belonging to the mapped points, the obtained label 640 isoutputted as an attribute.

To decide the attribute region, it is not necessarily check the all thepixel positions as the set points. The set points can be replaced withsome representative points appropriately selected from the pixel pointson the plane. Further, when the rough position of the desired region canbe known, only a single initial point can be set within the desiredregion.

Further, it is possible to cluster by deciding the attribute regions,without previously setting the set points. For instance, all the pixelcoordinates on the picture are inputted in sequence. As shown in FIG.64(a), when the track of the N-time mapped points belongs to anotherattribute region, the attribute at that point a_(k) can be decided byits attribute region. After the N-time transforms, if the mapped pointsdo not belongs to any other attribute regions, the point is a new setpoint of the attribute region. Therefore, the set point of the attributeregion is a point at which the first transform is executed, withoutbelonging to the other attribute regions.

Sixteen Embodiment

In this embodiment, the attribute region is decided by using somerepresentative set points.

The transform is executed to represent a picture by three dimensions, inwhich the pixel plane is represented by (x, y) and the luminance valueis represented by z. The previously predetermined mappings are allowedto correspond to each block obtained by dividing a picture into aplurality of blocks. The mappings are to transform the x and ydirections of the set point and the z direction of the luminance value.In the mapping which transforms a point, the mapping corresponding tothe block (to which the transformed point belongs) is used. Forinstance, when transformed to a mapping point (X, Y, Z) by mappingdefined by a set point (x, y, z), the mapping transform can be definedby the following affine transform as ##EQU5##

In this affine transform, the mapping is executed in such a way that thereduction and rotation in both the x and y directions can be madeaccording to coefficients a, b, c and d; the reduction in the zdirection can be made according to e; and the shift in the x and ydirections are made according to f, g and h.

The transform at the set points by mapping is executed by the transformin the x and y directions or by only in the z direction. Or else, thetransform is executed in all the X, Y, Z directions. The method ofclassification is selected according to what are transformed at the setpoints.

The x and y direction transform will be described in detail hereinbelowon the basis of an example, when the affix transform is used as ##EQU6##

First, as shown in FIG. 64(b), the method of using a range in which themapping points move will be explained. For instance, the positions of atleast n-time mapping points obtained midway during the N-time mappingpoints can be clustered by enclosing them by a rectangle. Without beinglimited only to a rectangle, the positions can be enclosed by any shape.In this method, it is possible to classify the mapping positions moreaccurately according to the given mapping points.

FIG. 65 is an example of a circuit for obtaining the range in which themapping points move in the x direction and for deciding whether theother points belong to the attribute represented by the mapping. Therange in which the mapping points move in the y direction can beobtained in the similar circuit. Further, it is possible to set arectangular region by ANDing both the ranges in the x and y directions.

In FIG. 65, a comparator 82 outputs "1" when the upper side inputthereto is larger than the lower side input thereto, and "0" in theother case. A portion 80 enclosed by dashed lines is a circuit forobtaining a maximum value; and a portion 90 enclosed by dashed lines isa circuit for obtaining a minimum value. A memory 49 stores thecoordinates of the N-time mapping points. Here, when the maximum valueat the current x point is denoted by ##EQU7## the comparator 82 comparesthis maximum value 87 with the coordinate x_(k) of a newly inputtedpoint x. If the coordinate x_(k) of newly input point x is larger, thecomparator 82 outputs "1" (as 83) In the case other than that, thecomparator outputs "0" (as 83). A switch 84 switches the output 85 tothe upper side input point x_(k) if the output 83 is at "1" and to##EQU8## in the case other than that. The output result 85 is stored ina memory 86 as ##EQU9##

The above-mentioned operation is repeated by N-times. Finally, a memory86 stores the maximum x-direction value of the attribute region as##EQU10##

A comparator 88 compares the coordinate of a point x_(now) whoseattribute is required to be checked with the maximum value 87 of thex-coordinate in sequence. When the maximum value 87 is larger, thecomparator 88 outputs "1". In the same way, the minimum value 96 of thex coordinate value can be obtained. When the coordinate of the pointx_(now) is larger than the output 96 of the memory 95, a comparator 97outputs "1". Finally, the two outputs 89 and 98 are inputted to an ANDcircuit 99, and the AND circuit 99 outputs an output 100 when x_(now) isincluded in the following range between: ##EQU11##

The second method is to use the number of periods. A track of the motionof the N-unit mapping points obtained from the first mapping to theN-time mapping with respect to one set point is referred to as a trackof the mapping points for the set point. The track of the mapping pointsfor the set point describes sometimes a periodic track, after a certainnumber k of mappings, where

    (kε{1, 2, . . . , N})

This implies that the mappings are clustered by use of a number mappingpoints describing a periodic track (orbit). Therefore, the standard ofthe clustering for attribute decision can be determined as the number ofperiods of the periodic track described for each set point. In thiscase, as shown in FIG. 64(c), the mapping points can be clustered. Inthis method, it is possible to classify the regions by taking intoaccount a regular pattern of the texture.

Third method is to use the shape of the periodical track, as shown inFIG. 64(d). In this method, since the mapping points are clustered byuse of the shape of the periodic track in addition to the periodicnumber, it is possible to classify the regions under consideration ofthe shape of the region.

When the pixel value at the set point is transformed, the transformedresults in the z direction are observed as the time series data.Further, as shown in FIG. 66, it is possible to classify the points onthe basis of the dispersion of the observed waveform and the fractaldimensions. Further, the above-mentioned three methods can be adoptedfor the change in the luminance value (in the z direction), instead ofthe positions (x and y directions) of the N-time mapping points. Whenthe position and the luminance value are both transformed, theabove-mentioned three methods can be adopted for both. Further, afterthe clustering has been made on the basis of the results of transform inboth the x and y directions, the texture can be analogized from thetime-series waveform in the z direction, as shown in FIG. 66. Further,it is possible to analogize the texture and the luminance value of theregion corresponding to the cluster on the basis of the n-time mappingpoint z_(n) in the z-direction of the mapping points belonging to thecluster.

In the above-mentioned embodiments, when the cluster (attribute region)to which the pixels a_(k) belong is decided, N-time mapping points ofthe pixels a_(k) are used. However, it is also possible to decide theattribute of the pixel a_(k) when n-time mapping points (midwayobtaining the N-time mapping points) are transformed to a certainattribute region. In this case, since it is not necessarily execute theN-time transforms, the quantity of calculations can be reduced.

When the regions are clustered by use of some representative points,without selecting all the pixels at the set points, there exist somepixels which have N-time mapping points belonging to none of theattribute regions of the set points. In this case, the non-decided pixelcan be decided as belonging to the cluster (the attribute region) whosedistance is the nearest from the coordinate of the non-decided pixel.Further, the non-decided pixel can be decided as belonging to thecluster (the attribute region) whose pixel is the nearest from theinitial coordinate of the non-decided pixel.

FIG. 67 is a flowchart showing the method of dividing the pixel regionaccording to the present invention.

The coordinates of all the pixels are inputted in sequence (in stepST10). Control transforms the coordinates C13 of the inputted pixels onthe basis of the given mapping data (in step ST11). Further, controldiscriminates whether a predetermined number of settings are transformed(in step ST14). If yes, control outputs the coordinates C17 of themapping points. Control decides the attribute of the pixel point on thebasis of the coordinate C17 of the mapping point, and outputs thedecided result C18 (in step ST15). Further, control decides the pixelvalue on the basis of the coordinates C17 of the mapping point, andoutputs the decided result C18 (in step ST17). Finally, controldiscriminates whether the attributes and the pixel values are obtainedfor all the pixels (in step ST16), ending the procedure.

FIG. 68 is a block diagram showing an apparatus for dividing the pixelregion according to the present invention. The point coordinates 70stored in storage means 69 and the mapping parameters 66 stored in otherstorage means 65 are inputted to transforming means 67. The coordinates68 of the mapping points are stored in storage means 69. Further, thepoint coordinates 70 are inputted to attribute deciding means 75 toobtain the attribute decision result 76. Further, the point coordinates70 are also inputted to pixel value deciding means 77 to obtain thepixel value 78.

The storage means 69 stores the initial positions of the set points andthe positions of the mapping points, as shown in FIG. 69. The set pointis transformed by the transform means 67 on the basis of the mappingdata 65 for realizing the similarity transform defined at the set point.The transformed result is stored in the storage means 69. Theabove-mentioned processing is repeated by predetermined N-times. By useof the N-time mapping points 70 for all the set points, the attributedeciding means 75 clusters the N-time mapping points for each set point.The pixel points are labeled by the cluster (attribute region) belongingto the N-time mapping points. The obtained labels 78 are outputted.Further, the transforming means 67 repeats the transforms by apredetermined number N of times. Further, the pixel value deciding means77 obtains the transformed luminance values (not dispersed) by use ofthe luminance transform of the N-time mapping points 70 at the initialpoints, and outputs the obtained values as the pixel values 78. As aresult, by use of the same transform results 70, the region division andthe reproduced picture can be both obtained. That is, since the regiondivision can be made while reproducing the picture, it is possible toreduce the amount of calculations required for region division.

Here, the set points stored in the storage means 69 are initial pointsarranged at all the pixel positions on the picture plane. However, asalready explained in the description of the fifteenth embodiment, thesetting points can be selected in the other ways. Further, the transformmeans 67 can be set in the same way as with the case of the fifteenthembodiment.

In the clustering of the attribute deciding step ST15 shown in FIG. 67,the near N-time mapping points can be classified into one cluster, onthe basis of the positions of the N-time mapping points at all the setpoints, as shown in FIG. 64(a). The clustering method can be automatizedby use of the well-known median method. The other clustering methods andthe already-explained three methods as explained in the fifteenthembodiment with reference to FIGS. 64(b), 64(c) and 64(d) can be used.In any method, it is necessary to store at least two mapping points asthe n-time mapping points, to decide the attribute region.

The criterion and the method of clustering can be selected, according tothe characteristics of the video signals and the use of the regiondivision. Further, it is also possible to select any desired regionsadaptively.

The pixel value at each pixel can be decided by transforming the pixelvalue at the mapping point. Any initial pixel value is given and thepixel value is transformed on the basis of the mapping given accordingto the pixel position. The pixel value obtained after n-time transformsis referred to as an n-time mapping pixel value. The n-time mappingpixel value can be obtained by transforming the (n-1) mapping pixelvalue in the mapping as defined in the n-time mapping points. When firstgiven initial pixel value is equal to the actual pixel value as shown by(a) in FIG. 70, the n-time mapping pixel value will not diverse everafter having mapped many times. For instance, when the actual pixelvalues lie between 0 and 255 values, the n-time mapping pixel valuesalso ranges from 0 to 255. In contrast with this, when first giveninitial pixel value is different from the actual pixel value, the n-timemapping pixel value diverges after having mapped many times. Forinstance, when the actual pixel values lie between 0 and 255 values, then-time mapping pixel values lie out of the range from 0 to 255, as shownby (b) in FIG. 70. Therefore, in order to obtain the correct pixelvalues, it is necessary to obtain an initial pixel value in such a waythat the n-time mapping pixel value will not diverse (because n-timemapping pixel values can be transformed only within the actual range ofthe pixel values). The transform of the pixel value is given accordingto the mapping point position. Therefore, it is possible to decide thepixel value by utilizing the transform, as it is, used for the attributedeciding means. Further, in case one pixel value cannot be decided afterthe given N-time mappings and therefore a plurality of candidates existas the reproduced pixel values, an average value or any one of them isdecided. Further, the transforms can be repeated until only one pixelvalue can be decided. Since the repetitive transforms for deciding thepixel value can be used in common for the transform for deciding theattribute, it is possible to reduce the quantity of calculations, ascompared with the prior art case where the two transforms are calculatedseparately.

Further, it is unnecessary to always execute both the picturereproduction and the region division. According to the necessity, anyone of both can be executed. For instance, when an original picture hasbeen already obtained, only the region division is sufficient.Therefore, when there exists any one of the apparatus according to thepresent invention, it is possible to use the apparatus as the picturereproducing apparatus and as the picture region dividing apparatus,separately.

FIG. 71 shows an example of a transmitter-receiver for simply informingthe receiver side of a region in a picture. Form the original picture onthe transmission side, the relationship between the region to be shownand the cluster is checked. As a result, the region to be shown and theshape of the corresponding cluster are represented by a simple graphicform, and the graphic form and the position are transmitted. Or else,when the labeling method of the clusters is previously determined, onlythe labeling can be transmitted. In this labeling method, for instance,when the pixels are scanned from the upper left side, it is possible touse the sequence of appearances of the clusters to which the pixelvalues belong.

In the example shown in FIG. 71, a graphic form and its position aretransmitted on the basis of only the upper right side coordinates of arectangle which encloses the cluster and the vertical and horizontallengths of the rectangle, or a cluster label (e.g., #4) is transmitted.In this example, when the enclosed graphic form is limited to a square,the data quantity can be further reduced. Further, when enclosed by acircle, it is sufficient when only a central coordinate and a radiusthereof are transmitted. On the reception side, it is possible to knowwhat the region is, on the basis of the position and the size of theobtained graphic form and the arrangement pattern of the N-time mappingpoints.

FIG. 72 shows an example for coding a picture. Inputted video signals110 are stored in storage means 111. The video signals 112 outputted bythe storage means 111 are inputted to coding means 113 for fractalcoding. The coded data 114 are outputted from the coding means 113.Further, coded data 114 are stored in storage means 115, and theninputted to region dividing means (the gist of the present invention)117 as the given mapping data 116. The region dividing means 117reproduces the one pixel value and outputs it as the reproduced picturevalue 118. Further, the region dividing means 117 outputs the regiondivision result 119 of one pixel at the same time to difference codingmeans 120. The reproduced pixel value 118 outputted by the regiondividing means 117 and the difference value 121 outputted by the storingmeans 111 are both inputted to difference coding means 120. Thedifferential signal 121 is coded by the difference coding means 120 onthe basis of the region division result 119, and outputs it as the codeddata 122. The region division result 110 are used as the control signalsfor coding the difference. For instance, since there exists such anature that the difference signal becomes large in the region of acomplicated texture but small in a flat region, when the texture regionand the flat region are classified by utilization of the nature andfurther the different coding methods are adopted respectively, thepicture quality of the reproduced picture can be improved. Further, inthis example, since the processing of all the means (except the fractalcoding means) can be executed in unit of pixel, no memory is necessary.However, when the difference coding means is required to be executed inunit of several pixels, a corresponding memory is necessary. Asdescribed above, when the method according to the present invention isadopted, it is possible to realize the method and apparatus for codingpictures adaptively.

FIG. 74 is a block diagram showing a decoder for decoding the data codedby the coder as shown in FIG. 72. The coded data 123 outputted from thecoding means are inputted to storage means 124. The coded data 125outputted from the storage means 124 are inputted to region dividingmeans (the gist of the present invention) as the given mapping data. Thepixel value 127 reproduced by the region dividing means 126 areoutputted to an adder 128. Further, the region division result 129 ofthe region dividing means 126 and the difference codes 130 coded by thedifference coding means (not shown) are inputted to difference decodingmeans 131 to reproduce the difference value 132. The reproduceddifference value 132 and the fractal-reproduced pixel value 127 aregiven to an adder 128, to obtain the final reproduced pixel value 133.

The embodiments of the present invention will be described hereinbelowwith reference to the attached drawings.

FIG. 74 is a flowchart showing the procedure of the method ofrepresenting the region boundary of the picture according to the presentinvention. In step ST20, control inputs picture data 134 and thendivides them into regions. After that, control inputs all the blocks insequence. In step ST21, control takes a block R_(k). In step ST22,control discriminates whether a desired region boundary exists in theblock R_(k). If exists, in-step ST23, control gives the block number kto a pointer P_(m), and proceeds to step ST24. If the region boundarydose not exist or after the pointer has been attached to the blockhaving the region boundary, control discriminates whether the boundarydiscrimination has been completed for all the blocks in step ST24. Ifnot yet completed, control repeats the same procedure beginning from thestp ST21. If completed, control outputs the pointed area position andthe mapping data, ending the procedure.

FIG. 75 is a block diagram showing a picture region boundaryrepresenting apparatus according to the present invention. The mappingparameter 136 are inputted from a given mapping memory 135 to regiondividing means 137 for region division processing. The region divisionresult 138 are inputted to region boundary detecting means 139, todetect a block having the region boundary corresponding to the requiredregion 140. The position 141 of the detected area including the regionboundary is outputted from the region boundary detecting means 139.Further, the position data 141 and the mapping parameter data 136 areinputted to control means 142, to output the mapping parameter data 143allowed to correspond to the block having the desired region boundary.

Here, the movement of the coordinate point in the block having a regionboundary will be explained. In FIG. 76, the mapping between the block144 and the similar region 145 is so selected that the attributes 159and 160 at points in the block 144 match each other. When two initialpoints 146 and 147 in the block 144 are transformed to the mappingpoints 148 and 149 by mapping processing 156 and 157, the distances d1'and d2' between the mapping points 148 and 149 (after transformed) andthe boundary 158 are larger than the distances d1 and d2 between the twoinitial points 146 and 147 (before transformed) and the region boundary158. In other words, the mapping points move gradually away from theboundary by transforms. This phenomenon continues, until the coordinatesof the mapping point moves to the block which does not have the regionboundary 158. Therefore, when the transforms are repeated, the mappingpoints of all the initial points in the block 144 having the regionboundary 158 are transformed to the block having no region boundarysooner or later.

Further, the movement of the coordinates of a point in a block having noregion boundary will be explained with reference to FIG. 77. In thiscase, the relationship between the block 161 and the similar region 162is so selected that the boundary 168 is not included. Therefore, thepoints 163 and 164 in the block 161 are transformed to the mappingpoints 165 and 166 by the mapping processing 169 and 170. Here, althoughthe coordinates of the mapping point 164 are transformed into the pointp' 166 in the block 167 having the region boundary 168, as explained inFIG. 76, the mapping point is transformed in a block having no regionboundary sooner or later.

As described above, there occurs a phenomenon such that a point in oneregion moves around in a limited range in the region. The attribute ofan initial point can be decided by clustering this range, and furtherthe range can be divided for each region. Further, the region boundarycan be found by dividing the region.

To represent the region boundary divided as described above, the mappingallowed to correspond to the block having the region boundary is used.As already explained, in FIG. 78, the two mapping points 175 and 176 ofthe two initial points 173 and 174 in the block 172 having the regionboundary 171 are transformed out of the block having the region boundarysooner or later. Therefore, when the inside of the region boundary 172is determined as an attribute A and the outside of the region boundary172 is determined as an attribute B, as far as only the initial point inthe block having the region boundary 171 is decided as A or B, it ispossible to obtain a detailed region boundary 171.

In the following description, in correspondence to the fractal coding,the area is referred to as the block, and the similar block allowed tocorrespond to each block is referred to as each similar block forunification. In this case, the blocks are never overlapped with eachother (the intersection is an empty set), and further a picture iscovered with all the blocks (the coupled blocks form an overall pictureplane). Although not specified, the shape is determined as a square inthe following description, for instance.

Since the transform in the method of detecting the parameter of theregion boundary can be expressed by the same formula (3) as alreadyexplained, the formula (4) (affine transform) will be explained indetail on the basis of an embodiment. Further, in the followingdescription, mapping is referred to as region boundary parameter.

By use of the region boundary parameter, the region is divided, and adesired region is selected as a result of the region division. Further,a block (referred to as a boundary block, hereinafter) having a boundaryportion is detected in the selected region. The position of the boundaryblock and the parameter (referred to as region boundary parameter,hereinafter) of the boundary block are coded, and used as the regionboundary data.

As the retrieval range of the similar block, all the picture or alimited range thereof can be used. Further, the retrieval range can beset around the block. The similar block can be decided by selecting asimilar block having the least square error or a similar block having asquare error less than a threshold level or by use of the fractaldimension or dispersion. When the threshold value is set, it is possibleto reduce the amount of calculations for retrieving the similar block.In the following description, the retrieval block is set to a limitedrange in the periphery of the block, and the case where the square (thesecond power) error is used as a scale will be explained.

On the other hand, the some conditions can be set so that an unclearboundary can not be detected and, as a result, a similar block will notbe decided from a different region. For instance, in FIG. 79, the casewhere the square errors between the block 177 of a flat region A and ablock D4 of another region B becomes the minimum values in the retrievalrange is taken into account. The square error becomes smaller in theorder of the blocks of D4<D1<D2<D3.

In the flat region A, since the square error is small during theretrieval, the similar block is not selected from another region soeasily. However, when a difference in luminance is small and thereforethe region boundary 178 is not clear as shown in FIG. 79, since theluminance of another adjacent region B is similar, a similar block D4can be selected from another region B having the minimum square error.When retrieved from the periphery of the coded block 177 shown in FIG.79 in the order of 1 to 4, the square error of the block D3 having theregion boundary increases, as compared with the square error of theblock D2 having no region boundary, so that the this status can bedetected by the following two conditions:

the square error between the block and the similar block is equal to orless than a threshold value Th, and further

the square error between the current block and the similar blockincrease abruptly in comparison with the square error between thepreceding block and the similar block.

Therefore, since the square can be detected on the basis of the aboveconditions, the retrieval is completed when these conditions have beensatisfied, and the block having the minimum square error before now isdecided as the similar block D1.

On the other hand, there exists such a method that a similar blockrepresentative of a flat region is previously set to facilitate ofdeciding the attribute. This method will be explained with reference toFIG. 80.

Before the peripheral coded blocks are retrieved, a difference in thesquare error between each block and the similar block D_(c)(representative similar block in the previously set region A) isobtained. When this error is smaller to some extent, the blocks areconsidered to belong to the same region A, and the mapping A1 to A5 tothe representative block D_(c) are executed as the mapping to the block.Therefore, since the mapping points transformed in this method can becollected effectively in the set similar block D_(c), the clustering canbe executed easily.

FIG. 81 is a flowchart showing the procedure of a method of reproducingthe boundary represented by the picture region boundary representingmethod according to the present invention.

First in step ST25, control inputs a desired region boundary blockR_(m). Further, control inputs the pixel a₀ (179) in the region R_(m).In step ST26, control transforms the pixel a₀ in accordance with themapping allowed to correspond to R_(m). In step ST27, controldiscriminates whether the transformed mapping point a_(ij) (180) lies ina desired region or not. Since the data for deciding the outside and theinside of the boundary block in the desired region can be given togetherwith the position data, when the mapping point a_(ij) moves out of theboundary block, control discriminates this, so that control proceeds tostep ST28. If staying in the boundary block, since cannot bediscriminated at this time, control obtains the mapping point a_(ij)repeatedly in steps ST26 and 27, until the pixel goes out of theboundary block. In step ST28, control discriminates whether theattribute of all the pixels in R_(m) can be decided. If all the pixelattributes are decided, control proceeds to step ST29. If not decidedyet, control repeats the steps ST26 to ST28 to execute the similarprocessing for the succeeding pixel. In step ST29, when the regionboundary has been obtained for all the designated blocks, control ends.If not yet obtained, control repeats the procedure for the succeedingcoded block beginning from the step ST25.

FIG. 82 is a block diagram showing an apparatus for reproducing theboundary represented by the picture region boundary representingapparatus according to the present invention.

The mapping data 181 of the desired region boundary block are inputtedto transform means 182. The mapping points 183 transformed by thetransform means 182 are stored in the storage means 184. The storedmapping point 185 and the region boundary position data 186 are inputtedto attribute deciding means 187 to decide the attribute of the mappingpoint 185 (i.e., whether the mapping point lies outside or inside adesignated region). Further, if the attribute cannot be decided, themapping point 185 is inputted again to the transform means 182,repeating the similar processing. If the attribute can be decided, theattribute deciding means 187 outputs the region boundary 188 as thefinal output.

When the region boundary is reproduced, only the pixels within theboundary block are transformed on the basis of the position data of theboundary block. The attribute decided at this time is either one of theinside and the outside of the boundary. After the attributes of all thepixels in the boundary block have been decided, the detailed boundary ofthe region can be reproduced.

When the boundary block position and the mapping are coded in variablelength, these data can be represented by a smaller number of bits. Atthis time, in the present invention, the variable-length coding means(or method) is added to the final output of the image boundaryrepresenting apparatus (or method), and the decoding means (or method)is added to the input of the reproducing apparatus (or method).

The coding/decoding can be coded together by using the parallel shiftparameter and the position data as one data source, or separately. Forinstance, Huffman coding can be considered for the parallel shiftparameter, and run-length coding or chain coding can be considered forthe position data.

When attribute numbers are used as one of the used data, instead of theboundary block position, it is possible to reduced the total regionboundary data. In the reproduction case, the attributes are decided forall the pixels of the picture, and the region boundary can be obtainedby the decided attribute numbers.

There exists such a case that other data can be inputted, instead of theselection of any desired region.

For instance, the first case is as follows: although the regionpreviously required to be transmitted is extracted in unit of block, theregion boundary is required to be represented in more detail beyond theblock unit. In this case, the region dividing method and apparatus asproposed in the present invention are not necessary. Further, since theretrieval range of the similar block to the boundary block of thepreviously given region can be limited in a previously extracted region,the quantity of calculations can be reduced. Further, since the otherunnecessary regions are almost not included in the retrieval range, thepossibility that the similar block is selected from another regionerroneously becomes low.

The second case is as follows: a boundary block previously required tobe transmitted is given. In this case, the retrieval range of thesimilar block can be limited and further the boundary block is notrequired to be detected, as already explained. In addition, the quantityof calculations can be reduced.

FIG. 83 is a flowchart showing another method of reproducing the regionboundary, which is different from that already explained with referencein FIG. 81.

In step ST30, control transforms pixels in the desired region boundaryblock R_(m) inversely on the basis of the parameter of the desiredregion boundary block R_(m). In other words, the pixel of the similarblock corresponding to each pixel of the block is transformed andspecified, and then the block pixel is replaced with a specified pixel.This transform step is repeated by a predetermined N-times. In stepST31, control discriminates whether the N-time transforms has beencompleted, and proceeds to step ST32. In step ST32, controldiscriminates whether all the designated region boundaries have beeninversely transformed. If yes, control ends the procedure. If not,control proceeds to the succeeding step to repeat the inverse transformbeginning from the step ST30.

The principle of this will be explained with reference to FIG. 84. Inthe reproduction principle as already explained, since the mapping ismade by transforming a block a₁ to a similar block a₂ larger than theblock a₁, the distance between the mapping point and the boundaryincreases as shown in FIG. 84(a), the phenomenon that the mapping pointscan be gathered on the inside of the region A is utilized. In this case,however, the reproduction method uses the inverse transform of the samemapping. In other words, as shown in FIG. 84(b), each pixel of thesimilar block is transformed to each pixel of the block. Therefore, when"0" and "1" are allocated to the pixel values of the blocks of theboundary block and the other block, when the inverse transform isexecuted for reduction as shown in FIG. 84(b), more detailed lines arereproduced gradually as shown in FIG. 84(c). By repeating this, asegment picture which represents a region boundary can be obtainedfinally.

In this reproducing method and apparatus, since the same regionparameter can be used for representing the region shape obtained by theregion boundary representing method and apparatus according to thepresent invention, the data indicating the inside and the outside of theregion is not necessary. Therefore, in this reproducing method, it ispossible to further reduce the region boundary data.

Two systems which can be realized by utilization of the presentinvention will be described hereinbelow by way of example.

FIG. 85 shows a system for performing radio communications between twoterminals. Since the quantity of transmittable data is very small in thecase of the radio communications, as compared with the cablecommunications, the compression technique for video signals of huge dataquantity is indispensable. Therefore, when pictures are required to betransmitted each other, video signals are compressed at each terminal;the compressed picture data are received each other; and the picturesare reproduced at each terminal, respectively. In this case, inparticular when the picture data are compressed, if the region boundaryrepresenting method according to the present invention is used, it ispossible to realize effective communications according to the usage, byextracting only a specific region, by compressing only the regionrequired to be transmitted, or by reproducing a picture by distributingmany bits to only an important region (to obtain a clear picture), etc.

Further, a picture synthesizing tool by use of the picture regiondividing method according to the present invention will be describedhereinbelow. When the present invention is utilized, a picture can beformed by synthesizing the compressed data. FIG. 86 shows an example ofthis system. In this system, some fractal-coded compressed video dataare previously stored in a disk 189. The user reads necessary video datafrom the disk 189 and reproduces pictures and display them on a displayunit 190. Here, for instance, when a different picture is required toform by specifying objects on two different pictures, only a regionclicked by the user on the picture is extracted by using the regiondividing method according to the present invention (the extractingmethod is described in the first embodiment), to detect a block coveringthe region. Then, the extracted region is arranged at any desiredposition to form a desired synthesized picture. As well understood fromthe principle of region division, since the mapping points in one regioncan be represented by use of the pixels in the region, as far as thereare the parameters of the region, the region can be reproduced.Simultaneously, the parameters of the region boundary block are writtenat the addresses corresponding to the desired position, to form thecompressed data of a synthesized picture. When the compressed data arereproduced, the desired synthesized picture as shown can be obtained.This system can be used for the preceding example (shown in FIG. 85) inwhich the radio receiver-transmitters are used.

In this tool, it is unnecessary to compress the synthesized pictureagain. Further, the compressed data of the synthesized picture can besubstituted by the address indicative of the desired region in theoriginal picture data. In many cases, the synthesized pictures can bestored effectively.

What is claimed is:
 1. A method for image representation such asdecoding using compressed image data, wherein an image is represented asa pixel value provided at each pixel in an image plane which is dividedinto a plurality of blocks, and compressed data include at leastposition data of a similar region about each of said blocks andconversion data of said pixel value, comprising:a) a step of setting aninitial value of said pixel value by applying to a pixel positionmapping points which are represented by coordinates and said pixel valueof said image plane; b) a step of performing a map in which each ofmapping points moves from a block including said mapping points to acorresponding position in the similar region, and said pixel value isconverted at the same time, wherein each of said mapping points isdirectly representative of a position of a pixel; c) a step of repeatingsaid map; d) a step of judging said mapping points as a positivedivergence when a pixel value of the mapping point exceeds apredetermined uppermost value, judging said mapping points as a negativedivergence when a pixel value of the mapping point goes below apredetermined lowermost value, and judging mapping points not to bedivergent when the mapping point stays between said predetermineduppermost and lowermost values even though a predetermined number ofmaps are repeated; and a step of changing said initial value by settingthe pixel value from an initial value until judged not to be divergentor at a boundary value between initial values of said positivedivergence and said negative divergence.
 2. An apparatus for imagerepresentation such as decoding using compressed image data, wherein animage is represented as a pixel value provided at each pixel in an imageplane which is divided into a plurality of blocks, and compressed dataincluding at least position data of a similar region about each of saidblocks and conversion data of said pixel value, comprising:a) means forholding said compressed data; b) means for setting an initial value ofsaid pixel value by applying to a pixel position mapping points, whichare represented by coordinates, and said pixel value of said imageplane; c) means for holding said pixel value and a position of saidmapping points; d) means for performing a map in which each of themapping points moves from a block including said mapping points to acorresponding position in the similar region, and said pixel value isconverted at the same time, wherein each of the mapping points isdirectly representative of a position of a pixel; e) means for repeatingsaid map; f) means for judging a mapping point as a positive divergencewhen a pixel value of the mapping point exceeds a predetermineduppermost value, judging the mapping point as a negative divergence whena pixel value of the mapping points drops below a predeterminedlowermost value, and judging the mapping point not to be divergent whenthe mapping point stays between said predetermined uppermost andlowermost values even though a predetermined number of maps arerepeated; g) means for changing said initial value by setting the pixelvalue from an initial value until judged not to be divergent or at aboundary value between initial values of said positive divergence andsaid negative divergence; and h) means for holding said pixel value.